Recovery of hydrogen halides in dry development of photoresists

Abstract

A method and apparatus are provided for the use and / or recovery of halogen-containing etchants in dry vapor phase development of metal oxide photoresists. In particular, the method specifically prepares a limited amount of etchant for dry development, supplied in a static quantity. The etchant may be a hydrogen halide such as hydrogen bromide. Furthermore, the method and apparatus facilitate the recycling of the etchant by techniques for capture, purification, and reuse.

Description

TECHNICAL FIELD

[0001] INCORPORATION BY REFERENCE The PCT Request is filed concurrently with this specification as part of the present application. Each application to which the present application claims benefit or priority that is identified in this concurrently filed PCT Request is incorporated herein by reference in its entirety for all purposes. BACKGROUND ART

[0002] Fabrication of semiconductor devices such as integrated circuits is a multi-step process that includes photolithography. Generally, this process includes steps of depositing materials on a wafer, and patterning the materials via lithographic techniques to form structural features (e.g., transistors and circuits) of the semiconductor device. Steps of a typical photolithography process include preparing a substrate, applying a photoresist by spin coating or the like, exposing the photoresist in a desired pattern to dissolve the exposed regions of the photoresist to some extent with a developer, developing the photoresist pattern by applying the developer to remove either the exposed or unexposed regions of the photoresist, and subsequent processing to create features on the regions of the substrate where the photoresist has been removed, by etching or material deposition or the like.

[0003] The evolution of semiconductor design has created a need for, and been driven by, the ability to form ever finer features on semiconductor substrate materials. One challenge in manufacturing devices with such fine features is the ability to reliably and reproducibly fabricate photolithography masks with sufficient resolution. Current photolithography processes typically use 193 nm ultraviolet (UV) light to expose a photoresist. The fact that the light has a wavelength significantly larger than the desired size of the features to be created on the semiconductor substrate creates inherent problems. Achieving feature sizes smaller than the wavelength of the light requires the use of complex resolution enhancement techniques such as multi-patterning. Accordingly, there is great interest and ongoing research in developing photolithography technologies that use shorter wavelength light, such as extreme ultraviolet (EUV) having a wavelength of 10 nm to 15 nm, for example 13.5 nm.

[0004] However, EUV photolithography processes may present challenges including low power output and inefficient absorption of EUV photons by thin resist layers. Accordingly, there remains a need for an improved EUV photoresist process that more efficiently produces materials with desired properties.

[0005] The description of the background art provided herein is for the purpose of generally presenting the context of the present disclosure. To the extent described in this Background section, the work of the present inventors, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are not admitted as prior art to the present disclosure, either expressly or implicitly. SUMMARY OF THE INVENTION

[0006] This disclosure relates to a method and apparatus for the efficient utilization, recycling, and / or recovery of halogen-containing etchants used in dry vapor phase development of metal oxide photoresists. In particular, the method specifically optimizes the dry development results by adjusting and limiting the amount of etchant reagent for dry development to a static amount, substantially reducing the amount of etchant required per wafer. The etchant may be a hydrogen halide. This method avoids a continuous flow of hydrogen halides, such as hydrogen bromide, which consumes an excess amount of etchant. The method and apparatus also facilitate the preservation of hydrogen halide reagents by recirculating or capturing excess reagent from dry development, which can then be purified and reused. In particular, any excess hydrogen halide may be captured upstream of the vacuum pump in the process chamber and then recirculated back into the process chamber for reuse, or captured downstream of the vacuum pump for further processing. The etchant may be hydrogen bromide, hydrogen chloride, trimethylsilyl bromide, or trimethylsilyl chloride.

[0007] Accordingly, in a first embodiment, the present disclosure encompasses a method for dry developing a semiconductor substrate. In some embodiments, the method includes the steps of: providing a photopatterned metal oxide EUV resist on a substrate layer of a semiconductor substrate in a process chamber, the photopatterned metal oxide EUV resist comprising EUV-exposed and EUV-unexposed portions; calculating a stoichiometric amount of halogen-containing etchant to decompose the EUV-unexposed portions of the photopatterned metal oxide EUV resist into water and volatile metal halides; and dry developing the photopatterned metal oxide EUV resist by selectively removing the EUV-unexposed portions of the photopatterned metal oxide EUV resist by exposure to a certain amount of halogen-containing etchant to form a resist hard mask from the EUV-exposed portions, wherein the amount of halogen-containing etchant is less than 50 times the stoichiometric amount calculated in step b); and step c) is a plasma-free thermal process.

[0008] In some embodiments, the amount of halogen-containing etching agent is less than 10 times the stoichiometric amount.

[0009] In some embodiments, the amount of halogen-containing etching agent in step c) is supplied at a rate of about 300 sccm to about 2,000 sccm for about 1 to 15 seconds.

[0010] In some embodiments, the method also includes the step of immersing a photopatterned metal oxide EUV resist in a halogen-containing etchant for about 1 to about 120 seconds.

[0011] In some embodiments, the process chamber includes a pedestal, side walls, and a showerhead.

[0012] In some embodiments, the side walls and showerhead are maintained at a first temperature, and the pedestal is maintained at a second temperature, with the first temperature being higher than the second temperature.

[0013] In some embodiments, the photopatterned metal oxide EUV resist is an organotin oxide.

[0014] In some embodiments, the halogen-containing etching agent is hydrogen halide.

[0015] In some embodiments, the hydrogen halide is hydrogen bromide or hydrogen chloride.

[0016] In some embodiments, the halogen-containing etching agent is trimethylsilyl bromide or trimethylsilyl chloride.

[0017] In a second embodiment, the Disclosure comprises a method for recycling halogen-containing etchants from the dry development of a resist. In some embodiments, the method includes the steps of: providing a photopatterned metal oxide EUV resist on a substrate layer of a semiconductor substrate in a process chamber, the photopatterned metal oxide EUV resist comprising EUV-exposed and non-EUV-exposed portions; dry developing the photopatterned metal oxide EUV resist by selectively removing the non-EUV-exposed portions of the photopatterned metal oxide EUV resist by exposure to a halogen-containing etchant to form a resist hard mask from the EUV-exposed portions, thereby generating volatile byproducts and excess halogen-containing etchant; removing the volatile byproducts and excess halogen-containing etchant from the process chamber; purifying the excess halogen-containing etchant by condensation, absorption, or a combination thereof to remove volatile byproducts and recover the excess halogen-containing etchant, thereby forming a recovered halogen-containing etchant; and returning the recovered halogen-containing etchant to the process chamber for reuse, wherein step b) is a plasma-free thermal process.

[0018] In some embodiments, the volatile by-products include water, metal halides, or combinations thereof.

[0019] In some embodiments, the photopatterned metal oxide EUV resist is an organotin oxide.

[0020] In some embodiments, the halogen-containing etching agent is hydrogen halide.

[0021] In some embodiments, the hydrogen halide is hydrogen bromide or hydrogen chloride.

[0022] In some embodiments, the halogen-containing etching agent is trimethylsilyl chloride or trimethylsilyl bromide.

[0023] In some embodiments, the exposure to the halogen-containing etchant in step b) is exposure to an amount of halogen-containing etchant less than 50 times the stoichiometric amount calculated to decompose the EUV-unexposed portions of the photopatterned metal oxide EUV resist into water and volatile metal halides.

[0024] In a third embodiment, the disclosure includes a method for recovering a halogen-containing etchant from the dry development of a resist. In some embodiments, the method comprises the steps of: providing a photopatterned metal oxide EUV resist on a substrate layer of a semiconductor substrate in a process chamber, the photopatterned metal oxide EUV resist comprising EUV-exposed and non-EUV-exposed portions; dry developing the photopatterned metal oxide EUV resist by selectively removing the non-EUV-exposed portions of the photopatterned metal oxide EUV resist by exposure to a halogen-containing etchant to form a resist hard mask from the EUV-exposed portions, thereby generating an impure excess of halogen-containing etchant, the impure excess of halogen-containing etchant being a halogen-containing etchant contaminated with volatile byproducts; removing the impure excess of halogen-containing etchant from the process chamber; optionally separating the volatile byproducts from the halogen-containing etchant by condensation, absorption, or a combination thereof; and collecting the impure excess of halogen-containing etchant by condensation, wherein step b) is a plasma-free thermal process.

[0025] In some embodiments, the excess impure halogen-containing etching agent collected in step e) is purified for reuse.

[0026] In some embodiments, the volatile by-products include water, metal halides, or combinations thereof.

[0027] In some embodiments, the photopatterned metal oxide EUV resist is an organotin oxide.

[0028] In some embodiments, the halogen-containing etching agent is hydrogen halide.

[0029] In some embodiments, the hydrogen halide is hydrogen bromide or hydrogen chloride.

[0030] In some embodiments, the halogen-containing etching agent is trimethylsilyl chloride or trimethylsilyl bromide.

[0031] In some embodiments, the exposure to the halogen-containing etchant in step b) is exposure to an amount of halogen-containing etchant less than 50 times the stoichiometric amount calculated to decompose the EUV-unexposed portions of the photopatterned metal oxide EUV resist into water and volatile metal halides.

[0032] In a fourth embodiment, the Disclosure comprises a method for processing by-products of dry development of a resist. In some embodiments, the method comprises the steps of: providing a photopatterned metal oxide EUV resist on a substrate layer of a semiconductor substrate in a process chamber operably coupled to a vacuum pump, the photopatterned metal oxide EUV resist comprising EUV-exposed and EUV-unexposed portions; dry developing the photopatterned metal oxide EUV resist by selectively removing the EUV-unexposed portions of the photopatterned metal oxide EUV resist by exposure to a halogen-containing etchant to form a resist hard mask from the EUV-exposed portions, thereby generating volatile by-products and excess halogen-containing etchant which are then discharged from the process chamber via exhaust from a vacuum pump; and processing the exhaust from the vacuum pump to process the volatile by-products and excess halogen-containing etchant to form neutralized by-products and neutralized halogen-containing etchant, wherein step b) is a plasma-free thermal process.

[0033] In some embodiments, step c) is the step of exposing the exhaust to an alkaline spray treatment.

[0034] In some embodiments, the photopatterned metal oxide EUV resist is an organotin oxide.

[0035] In some embodiments, the halogen-containing etching agent is hydrogen halide.

[0036] In some embodiments, the hydrogen halide is hydrogen bromide or hydrogen chloride.

[0037] In some embodiments, the halogen-containing etching agent is trimethylsilyl bromide or trimethylsilyl chloride.

[0038] In some embodiments, after step c), the neutralized halogen-containing etchant is converted back into a halogen-containing etchant for reuse in step b).

[0039] In some embodiments, the exposure to the halogen-containing etchant in step b) is exposure to an amount of halogen-containing etchant less than 50 times the stoichiometric amount calculated to decompose the EUV-unexposed portions of the photopatterned metal oxide EUV resist into water and volatile metal halides.

[0040] In a fifth embodiment, the disclosure includes an apparatus for recycling halogen-containing etchants during dry development of a resist. In some embodiments, the apparatus includes a process chamber having a substrate support, a gas recirculation inlet and a gas recirculation outlet; a halogen-containing etchant delivery line coupled to the process chamber; at least a first condenser and a second condenser, each individually coupled to the process chamber, the first and second condensers comprising an inner water-absorbing liner material and an outer temperature-adjustable jacket; a recirculation line configured to connect the first condenser, the second condenser, the gas recirculation inlet and gas recirculation outlet; a gas stirring module connected to the recirculation line; a vacuum pump; and a vacuum line coupled to the process chamber. A controller configured with instructions for processing a substrate, the instructions include a code for: providing a photopatterned metal oxide EUV resist on the substrate into a process chamber; developing the photopatterned metal oxide EUV resist by selectively removing a portion of the resist by exposure to a halogen-containing etchant to form a resist mask; guiding process gases and byproduct vapors from the process chamber to a first or second condenser; cooling the first or second condenser to capture water; forming a purified halogen-containing etchant stream; and recirculating the purified halogen-containing etchant stream into the process chamber via a recirculation line.

[0041] In some embodiments, the gas agitation module is a magnetically coupled turbofan.

[0042] In some embodiments, a first condenser is configured to receive process gas and by-product vapor from the process chamber, and the first condenser is cooled.

[0043] In some embodiments, the first condenser is cooled while the second condenser is heated for cleaning, collecting water and recycling hydrogen halides.

[0044] In some embodiments, the first and second condensers are operably connected to a vacuum pump.

[0045] In some embodiments, the first and second condensers are located upstream of the vacuum pump.

[0046] In some embodiments, the inner water-absorbing liner material is anhydrous aluminum oxide, silica gel, aluminosilicate, or a combination thereof.

[0047] In a sixth embodiment, the disclosure comprises an apparatus for recovering halogen-containing etchant during dry development of a resist. In some embodiments, the apparatus includes a process chamber having a substrate support; a halogen-containing etchant delivery line coupled to the process chamber; a vacuum pump comprising a vacuum pump inlet line coupled to the process chamber and a vacuum pump outlet line for removing exhaust; at least one cryogenic condenser coupled to the vacuum pump outlet line; and a controller configured with commands for processing a semiconductor substrate, the commands providing a photopatterned metal oxide EUV resist onto the substrate within the process chamber. The system includes a controller, which includes a code for developing a photopatterned metal oxide EUV resist by selectively removing a portion of the resist by exposure to a halogen-containing etchant to form a resist mask, and for recovering excess halogen-containing etchant by guiding the exhaust from the process chamber from a vacuum pump outlet line to a low-temperature condenser.

[0048] In some embodiments, the apparatus also includes a trap positioned between the vacuum pump and the cryogenic condenser, the trap being configured to collect liquid byproducts.

[0049] In a seventh embodiment, the present disclosure comprises an apparatus for processing by-products of dry development of resists. In some embodiments, the apparatus includes a process chamber having a substrate support; a halogen-containing etchant delivery line coupled to the process chamber; a vacuum pump comprising a vacuum pump inlet line coupled to the process chamber and a vacuum pump outlet line for removing exhaust; a detoxification module coupled to the vacuum pump outlet line; and a controller configured with instructions for processing a semiconductor substrate, the instructions including a code for providing a photopatterned metal oxide EUV resist onto the substrate in the process chamber, developing the photopatterned metal oxide EUV resist by selectively removing a portion of the resist by exposure to a halogen-containing etchant to form a resist mask, and directing the exhaust from the process chamber from the vacuum pump outlet line to the detoxification module to neutralize by-products.

[0050] In some embodiments, the detoxification module is an alkaline spray treatment system.

[0051] In some embodiments, the by-products include a halogen-containing etching agent.

[0052] These and other embodiments are described further below with reference to the drawings. [Brief explanation of the drawing]

[0053] [Figure 1] This is a flowchart of a conventional process for depositing, developing, and processing photoresist. [Figure 2A] This is a schematic cross-sectional view of a processing stage that includes the development and processing of photoresist. [Figure 2B] This is a schematic cross-sectional view of another processing stage, including the development and processing of the photoresist. [Figure 2C] This is a schematic cross-sectional view of yet another processing stage, including the development and processing of the photoresist. [Figure 3A] This figure shows a scanning electron microscope (SEM) image of a photoresist after dry development using hydrogen bromide, according to a specific disclosed embodiment. [Figure 3B] This figure shows a scanning electron microscope (SEM) image of a photoresist after dry development using trimethylsilyl chloride according to a specific disclosed embodiment. [Figure 4A] This is a schematic diagram of an exemplary system for recycling hydrogen halides from dry developer in a process chamber and upstream of a vacuum pump, according to a specific disclosed embodiment. [Figure 4B] This is a schematic diagram of an exemplary system for recovering hydrogen halides from dry development in a process chamber and downstream of a vacuum pump, according to a specific disclosed embodiment. [Figure 5] This is a schematic diagram of an exemplary system for processing by-products from dry development in a process chamber and downstream of a vacuum pump, according to a specific disclosed embodiment. [Figure 6] This is a schematic diagram of an exemplary process station for maintaining an environment suitable for performing photoresist development and other photoresist processing operations according to a specific disclosed embodiment. [Figure 7] This is a schematic diagram of an exemplary multi-station process tool suitable for performing the photoresist development and other photoresist processing operations described herein, according to a specific disclosed embodiment. [Figure 8] This is a schematic cross-sectional view of an exemplary inductively coupled plasma apparatus for carrying out specific embodiments and operations described herein, according to a particular disclosed embodiment. [Figure 9] This figure shows a semiconductor process cluster tool architecture having a vacuum transport module and a vacuum integrated deposition and patterning module that interfaces with a vacuum transport module, suitable for implementing the process described herein according to a specific disclosed embodiment. [Modes for carrying out the invention]

[0054] The following description includes numerous specific details to provide a complete understanding of the presented embodiments. The disclosed embodiments may be implemented with some or all of these specific details omitted. In other examples, well-known process behaviors are not described in detail so as not to unnecessarily obscure the disclosed embodiments. The disclosed embodiments are described in conjunction with specific embodiments, but it should be understood that this is not intended to limit the disclosed embodiments.

[0055] definition "Alkyl" and the prefix "alk" refer to branched or unbranched saturated hydrocarbon groups with 1 to 24 carbon atoms, such as methyl (Me), ethyl (Et), n-propyl (n-Pr or nPr), isopropyl (i-Pr or iPr), cyclopropyl, n-butyl (n-Bu or nBu), isobutyl (i-Bu or iBu), s-butyl (s-Bu or sBu), t-butyl (t-Bu or tBu), cyclobutyl, n-pentyl, isopentyl, s-pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, tetradecyl, hexadecyl, eicosyl, tetracosyl, etc. Alkyl groups are cyclic (e.g., C 3-24cycloalkyl) or acyclic. An alkyl group can be branched or unbranched. An alkyl group can also be substituted or unsubstituted. For example, an alkyl group can include haloalkyl, in which the alkyl group is substituted with one or more halo groups, as described herein. In another example, for an alkyl group having 1, 2, 3, or two or more carbon atoms, the alkyl group is (1)C 1-6 alkoxy (e.g., -O-Ak, where Ak is an optionally substituted C 1-6 alkyl); (2) amino (e.g., -NR N1 R N2 (wherein R N1 and R N2 are each independently H or optionally substituted alkyl, or R N1 and R N2 together with the nitrogen atom to which they are each attached form a heterocyclyl group); (3) aryl; (4) arylalkoxy (e.g., -O-Lk-Ar, where Lk is a divalent form of optionally substituted alkyl, and Ar is optionally substituted aryl); (5) acryloyl (e.g., -C(O)-Ar, where Ar is optionally substituted aryl); (6) cyano (e.g., -CN); (7) carboxaldehyde (e.g., -C(O)H); (8) carboxyl (e.g., -CO2H); (9)C 3-8 cycloalkyl (e.g., a monovalent saturated or unsaturated non-aromatic cyclic C 3-8(10) Hydrocarbon group; (11) Halo (e.g., F, Cl, Br, or I); (12) Heterocyclyl (e.g., unless otherwise specified, a 3, 4, 5, 6, or 7-membered ring containing 1, 2, 3, or 4 noncarbon heteroatoms such as nitrogen, oxygen, phosphorus, sulfur, or halo); (13) Heterocyclyloxy (e.g., -O-Het (wherein Het is a heterocyclyl as described herein)); (14) Heterocyclyl (e.g., -C(O)-Het (wherein Het is a heterocyclyl as described herein)); (15) Hydroxyl (e.g., -OH); (16) N-protected amino; (17) Nitro (e.g., -NO2); (18) Oxo (e.g., =O); (19) -CO2R A (In the formula, R A (a)C 1-6 Alkyl, (b)C 4-18 Aryl, and (c)(C 4-18 Ariel)C 1-6 Selected from the group consisting of alkyls (for example, -Lk-Ar (wherein Lk is the divalent form of an optionally substituted alkyl group and Ar is an optionally substituted aryl)); (19)-C(O)NR B R C (In the formula, R B and R C Each of them independently consists of (a) hydrogen and (b) C 1-6 Alkyl, (c)C 4-18 Aryl, and (d)(C 4-18 Ariel)C 1-6 Selected from the group consisting of alkyls (e.g., -Lk-Ar (wherein Lk is the divalent form of an optionally substituted alkyl group and Ar is an optionally substituted aryl)); and (20)-NR G R H (In the formula, R G and R H Each of these independently consists of (a) hydrogen, (b) an N protecting group, and (c) C 1-6 Alkyl, (d)C 2-6 Alkenyl (e.g., optionally substituted alkyl having one or more double bonds), (e)C 2-6Alkynyl (e.g., an optionally substituted alkyl having one or more triple bonds), (f)C 4-18 Aryl, (g)(C 4-18 Ariel)C 1-6 Alkyl (e.g., Lk-Ar (wherein Lk is the divalent form of an optionally substituted alkyl group, and Ar is an optionally substituted aryl group)), (h)C 3-8 Cycloalkyl, and (i)(C 3-8 Cycloalkyl)C 1-6 The alkyl group can be substituted with four substituents independently selected from the group consisting of alkyl groups (e.g., -Lk-Cy (wherein Lk is the divalent form of an optionally substituted alkyl group, and Cy is an optionally substituted cycloalkyl group as described herein)), and in one embodiment, two groups are not bonded to the nitrogen atom through the carbonyl group. The alkyl group may be a primary, secondary, or tertiary alkyl group substituted with one or more substituents (e.g., one or more halo or alkoxy). In some embodiments, the unsubstituted alkyl group is C 1-2 , C 1-3 , C 1-6 , C 1-12 , C 1-16 , C 1-18 , C 1-20 , C 1-24 , C 2-3 , C 2-6 , C 2-12 , C 2-16 , C 2-18 , C 2-20 , or C 2-24 It is an alkyl group.

[0056] The term "flow control hardware" generally refers to a component configured to fluidly connect one or more chemical sources to a processing chamber. Flow control hardware may include, for example, one or more mass flow controllers and / or valves. Examples of chemical sources include dielectric film precursor sources, halogen-containing precursor sources, reaction gas sources, and inert gas sources.

[0057] The term "form a gas mixture" generally refers to either or both mixing multiple gases before introducing them into a processing chamber, or mixing multiple gases within the processing chamber.

[0058] The term "inert gas" generally refers to a gaseous material that does not react with other chemicals in the processing chamber during substrate processing. Examples of inert gases include helium (He), neon (Ne), argon (Ar), krypton (Kr), and xenon (Xe), as well as nitrogen (N2) in some processes.

[0059] The term "plasma" generally refers to a gas containing cations, free radicals, and free electrons. The term "in-situ plasma" generally refers to plasma formed at a processing station within a processing chamber. The term "remote plasma" generally refers to plasma formed at a location away from the processing station within a processing chamber.

[0060] The term "plasma generator" generally refers to a combination of components that can be used to form a plasma. Exemplary components include a high-frequency power supply, an impedance matching network, and one or more electrodes.

[0061] The term "precursor" generally refers to chemical species adsorbed onto the substrate surface during the deposition process. The precursor is reacted with a reactant to convert the adsorbed precursor into a film layer.

[0062] The term "processing chamber" or "processing chamber" generally refers to an enclosure within which chemical and / or physical processes are carried out on a substrate. The pressure, substrate temperature, and atmospheric composition within the processing chamber can be controlled to perform the chemical and / or physical processes.

[0063] The term "processing tool" may generally refer to a machine comprising a processing chamber and other hardware configured to enable processing to be performed within the processing chamber.

[0064] The term "processing station" generally refers to a location within the processing chamber where the substrate is positioned during processing.

[0065] As used herein, the term “semiconductor substrate” refers to a substrate at any stage in the fabrication of a semiconductor device that contains semiconductor material somewhere within its structure. It is understood that the semiconductor material within a semiconductor substrate does not need to be exposed. A semiconductor wafer having multiple layers of other material (e.g., dielectric) covering the semiconductor material is an example of a semiconductor substrate. In the detailed description below, the disclosed mounting configurations are assumed to be mounted on a semiconductor wafer, such as a 200 mm, 300 mm, or 450 mm semiconductor wafer. However, the disclosed mounting configurations are not limited in this way. Workpieces may vary in shape, size, and material. In addition to semiconductor wafers, other workpieces that may utilize the disclosed mounting configurations include various articles such as printed circuit boards.

[0066] The mounting configurations disclosed herein describe the deposition of material onto a substrate, such as a wafer, substrate, or other workpiece. The workpiece may vary in shape, size, and material. In this application, the terms “semiconductor wafer,” “wafer,” “substrate,” “wafer substrate,” and “partially fabricated integrated circuit” are used interchangeably. Those skilled in the art will understand that the term “partially fabricated integrated circuit” may refer to a silicon wafer in the midst of any of the many stages of integrated circuit fabrication thereon. Wafers or substrates used in the semiconductor device industry typically have diameters of 200 mm, 300 mm, or 450 mm. Unless otherwise specified, the processing details enumerated herein (e.g., flow rate, power level, etc.) relate to processing a 300 mm diameter substrate, or processing a chamber configured to process a 300 mm diameter substrate and which can be appropriately scaled to substrates or chambers of other sizes. In addition to semiconductor wafers, other workpieces on which the mounting configurations disclosed herein may be used include various articles such as printed circuit boards. The processes and apparatus can be used for processing semiconductor devices, displays, LEDs, photovoltaic panels, and the like.

[0067] As used herein, the term “photoresist” and its derivatives refer to a photosensitive material used in processes such as photolithography, photoetching, or photoengraving to form a patterned coating on a surface. Photoresist materials change their solubility in a developer when exposed to light of a specific wavelength. A photoresist layer may consist of either positive (exposed areas become soluble) or negative (exposed areas become insoluble) photoresist materials.

[0068] For the purposes of this disclosure, the term "metal" as used in this context should be understood to mean a conductor having a maximum resistivity of 500 microohms / cm, including metals and conductive metal salts, in particular conductive metal nitrides, such as TiN.

[0069] As used herein, "metal oxide photoresist" or "metal oxide EUV resist" includes, but is not limited to, a semimetallic oxide photoresist, a metal oxide photoresist, or an organometallic oxide photoresist.

[0070] "Tin oxide" in this specification includes integer values ​​of x and y, as well as non-integer values ​​of x and y. x O y It is referred to as encompassing all possible stoichiometric possibilities. For example, "tin oxide" is given by formula SnO n The compound contains the following, where 1 ≤ n ≤ 2, and n can be an integer or a non-integer value. "Tin oxide" is SnO 1.8 Compounds that do not meet the stoichiometric composition may be included. "Tin oxide" also includes tin dioxide (SnO2 or stannous oxide) and tin monoxide (SnO or stannous oxide). "Tin oxide" also includes both natural and synthetic variants, and all possible crystalline and molecular structures. "Tin oxide" also includes amorphous tin oxide.

[0071] As used herein, the phrase “at least one of A, B, and C” should be interpreted as meaning (A or B or C) using the non-exclusive logic “or,” and not as meaning “at least one of A, at least one of B, and at least one of C.”

[0072] As used herein, the term “approximately” is understood to include slight increases and / or decreases beyond the enumerated values, such that these changes do not significantly affect the desired function of the parameter beyond the enumerated values. In some cases, “approximately” encompasses + / - 10% of any enumerated value. As used herein, the term qualifies any enumerated value, range of values, or endpoint of one or more ranges.

[0073] As used herein, the terms “top,” “bottom,” “upper,” “lower,” “above,” and “below” are used to provide relative relationships between structures. The use of these terms does not indicate or require that a particular structure must be located in a specific place within the apparatus.

[0074] Introduction and Context The hot dry developing process uses halogen-containing reagents such as hydrogen bromide (HBr), hydrogen chloride (HCl), chlorine (Cl2), bromine (Br2), trimethylsilyl chloride ((CH3)3SiCl), or trimethylsilyl bromide ((CH3)3SiBr) to treat metal oxide photoresists. Vapor etching of metal oxide photoresists can utilize a large excess of the halogen-containing reagent to remove tin-bonded crosslinking oxides and hydroxides (converting them to water) and form tin halides. When the halogen-containing reagent is HBr gas, conventionally, excess amounts exceeding 500 times the required amount can be used, which increases costs and the amount of chemical waste generated. An efficient dry developing technique that allows for the recovery of the halogen-containing reagent and / or reduces the amount of the halogen-containing reagent would be advantageous not only from a cost perspective but also from an environmental perspective.

[0075] Development of EUV resist According to various aspects of this disclosure, a photopatterned metal-containing photoresist is developed by exposure to a hydrogen halide-containing chemical. An EUV-sensitive metal or metal oxide-containing film, such as an organotin oxide, is placed on a semiconductor substrate. Various potential metal-containing photoresists may include, for example, photoresists containing tin, tellurium, or hafnium bonded to an organic ligand which is an alkyl group having 1 to 12 carbon atoms. The EUV-sensitive metal or metal oxide-containing film is directly patterned by EUV exposure in a vacuum atmosphere. The pattern is then developed to form a resist mask using a developer. In some embodiments, the developer is a dry developer. In some embodiments, the dry developer may contain hydrogen chloride (HCl), hydrogen bromide (HBr), or trimethylsilyl halides (or a mixture of two or more thereof), possibly less than 5% oxygen and / or hydrogen, mixed with an inert carrier gas such as argon (Ar), helium (He), or nitrogen (N2) (or a mixture of two or more thereof), typically argon (Ar), helium (He), or nitrogen (N2) (or a mixture of two or more thereof). For example, such a dry developer containing a hydrogen halide donating gas as described above can flow across or over a wafer having a latent image (photopatterned metal-containing photoresist) while the wafer is held at a temperature in the range of -40°C to 40°C after exposure in an EUV patterning operation. Such a dry development technique may be carried out in a chamber pressure environment in the range of about 5 mTorr to 600 mTorr while flowing a dry developer, such as a hydrogen and halide dry developer.

[0076] When a metal-containing photoresist is exposed to a desired lithography pattern, for example, in an EUV scanner or similar patterning equipment, the exposed wafer may be moved to a dry developing chamber to perform a dry developing process to remove its unexposed areas. In some implementations, the exposed wafer may undergo post-exposure firing (PEB), a thermal process that converts broken metallic bonds in the tin-based alkoxy resist, such as tin bonds, into metal-oxygen bonds, such as tin-oxygen bonds, thereby forming a material stoichiometrically close to a metal oxide, such as tin oxide, in the exposed areas. Unexposed areas in such a PEB may retain an alkyl ligand in one of the exposed valencies of the metal, for example, one of the four valencies of tin. PEB may be performed after the wafer is exposed but before the dry developing process is performed. A typical PEB may include, for example, a PEB in which the wafer is heated to one or more temperatures between 130°C and 250°C for a period of 30 to 240 seconds. In some examples, the PEB process may include multiple PEBs, such as an initial PEB execution as described above, followed by a second PEB execution in which the wafer may be heated to one or more temperatures between 200°C and 300°C over a time period of 30 to 240 seconds in a controlled ambient environment.

[0077] During the dry developing process, one or more dry developing gases can flow across the exposed surface of the wafer. The dry developing gases may be selected to selectively attack / etch either the exposed or unexposed regions of the wafer. For example, a halide-containing chemical, such as hydrogen bromide, can be used to selectively remove unexposed regions of a photoresist, such as an organotin resist, as described above. Such a halide-containing chemical may preferentially attack the tin-oxygen moieties where alkyl groups are still bonded to the tin atom, i.e., regions that were not exposed to EUV and were not modified. In contrast, alkyl groups that may have been present in the exposed regions may have been previously evicted from those exposed regions during the exposure process, and therefore, the halide-containing chemical may not attack (or attack minimally) the exposed regions. For example, in organotin resists, the developer may etch away any tin alkyls that may remain in the unexposed regions, while the more tin oxide-like portions that may remain in the exposed regions may generally remain intact.

[0078] Figure 1 is a flowchart of the steps of a conventional method for depositing, developing, and processing a photoresist. In block 102 of process 100, a layer of photoresist is deposited. This may be either a dry deposition process, such as a vapor deposition process, or a wet deposition process, such as a spin-on deposition process. In one embodiment, a metal-containing precursor is deposited as a solution by using a liquid-based spin-on technique. In another embodiment, the metal-containing precursor is deposited in vapor form by using a dry technique (e.g., chemical vapor deposition).

[0079] Photoresist films can be deposited on a substrate. Such films can be deposited by using a wet or dry deposition process in which a metal-containing precursor (e.g., a tin-containing precursor, such as any of those described herein) is provided in close proximity to the substrate. In one embodiment, the metal-containing precursor is deposited as a solution by using a liquid-based spin-on technique. In another embodiment, the metal-containing precursor is deposited in vapor form by using a dry technique (e.g., chemical vapor deposition). While this disclosure often indicates that the metal-containing precursor is a tin-containing precursor, other metal atoms can also be used.

[0080] The layers and films described herein are 1 × 10 7 cm 2 The material may contain elements (e.g., metallic or nonmetallic atoms) with a high light absorption cross-section, such as 1 / mol or more. Such elements can be provided by depositing one or more precursors to provide an imaging layer.

[0081] In some embodiments, the film is a radiation-sensitive film (e.g., an EUV-sensitive film). This film can then function as an EUV resist, as further described herein. In certain embodiments, the layer or film may include one or more ligands (e.g., EUV-unstable ligands) that can be removed, cut, or crosslinked by radiation (e.g., EUV or DUV radiation).

[0082] The precursor can provide a radiation-sensitive, patternable film (or a patternable, radiation-sensitive film or a photopatternable film). Such radiation can be provided by irradiating through a patterned mask, and may include EUV, DUV, or UV radiation, which is the radiation that is patterned thereon. The film itself is altered by exposure to such radiation, and as a result, the film may become radiation-sensitive or photosensitive. In certain embodiments, the precursor is an organometallic compound containing at least one metal center.

[0083] The precursor can have any useful number and type of ligands. In some embodiments, the ligands may be characterized by their ability to react in the presence of a reactant or in the presence of patterned radiation. For example, the precursor may include ligands that react with a reactant that can introduce a bond between metal centers (e.g., -O- bonds). In another example, the precursor may include ligands that desorb in the presence of patterned radiation.

[0084] The precursor may include a metal or metalloid or atom having a high patterning radiation absorption cross-section. In some embodiments, M is tin (Sn), bismuth (Bi), tellurium (Te), cesium (Cs), antimony (Sb), indium (In), molybdenum (Mo), hafnium (Hf), iodine (I), zirconium (Zr), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), silver (Ag), platinum (Pt), and lead (Pb).

[0085] In certain embodiments, the precursor includes tin. Non-limiting tin precursors include SnF2, SnH4, SnBr4, SnCl4, SnI4, tetramethyltin (SnMe4), tetraethyltin (SnEt4), trimethyltin chloride (SnMe3Cl), dimethyltin dichloride (SnMe2Cl2), methyltin trichloride (SnMeCl3), tetraalyltin, tetravinyltin, hexaphenyltin(IV) (Ph3Sn-SnPh3 (Ph is phenyl)), and dibutyldiphenyltin (SnBu2Ph2) ), trimethyl(phenyl)tin (SnMe3Ph), trimethyl(phenylethynyl)tin, tricyclohexyl tin hydride, tributyltin hydride (SnBu3H), dibutyltin diacetate (SnBu2(CH3COO)2), tin(II) acetylacetonate (Sn(acac)2), tributyltin ethoxide (SnBu3(OEt)), dibutyltin dimethoxide (SnBu2(OMe)2), tributyltin methoxide (SnBu3(OMe)) , tin(IV)tert-butoxide (Sn(t-BuO)4), n-butyltin tributoxide (Sn(n-Bu)(t-BuO)3), tetrakis(dimethylamino)tin (Sn(NMe2)4), tetrakis(ethylmethylamino)tin (Sn(NMeEt)4), tetrakis(diethylamino)tin(IV)(Sn(NEt2)4), (dimethylamino)trimethyltin(IV)(Sn(Me)3(NMe2), Sn(i-Pr)(NMe2)3, Sn(n-B Includes u)(NMe2)3, Sn(s-Bu)(NMe2)3, Sn(i-Bu)(NMe2)3, Sn(t-Bu)(NMe2)3, Sn(t-Bu)2(NMe2)2, Sn(t-Bu)(NEt2)3, Sn(tbba), Sn(II)(1,3-bis(1,1-dimethylethyl)-4,5-dimethyl-(4R,5R)-1,3,2-diazastanoridine-2-ylidene), or bis[bis(trimethylsilyl)amino]tin(Sn[N(SiMe3)2]2).

[0086] Exemplary deposition techniques (e.g., for films) include any of those described herein, such as ALD (e.g., thermal ALD and plasma-enhanced ALD), spin-coat deposition, PVD including PVD co-sputtering, CVD (e.g., PE-CVD or LP-CVD), sputtering deposition, electron beam deposition including electron beam co-evaporation, or combinations thereof, such as ALD having a CVD component, including a discontinuous ALD-like process where the precursor and reactant are separated temporally or spatially.

[0087] Further descriptions of precursors applicable to this disclosure and methods for depositing them as EUV photoresist films are described in International Application PCT / US19 / 31618, filed on 9 May 2019 and published as International Publication 2019 / 217749, entitled “METHODS FOR MAKING EUV PATTERNABLE HARD MASKS”. In addition to precursors and reactants, the thin film may include optional materials for modifying the chemical or physical properties of the film, such as to modify the film’s sensitivity to EUV or to increase its etching resistance. Such optional materials may be introduced by doping, etc., during vapor formation before deposition on the substrate, during deposition on the substrate, and / or after film deposition. In some embodiments, a mild, distant H2 plasma may be introduced to replace some Sn-L bonds with Sn-H, for example, which can increase the reactivity of the resist under EUV. In other embodiments, CO2 may be introduced to replace some Sn-O bonds with Sn-CO3 bonds, thereby improving resistance to wet development.

[0088] Various atoms present in the precursor and / or the reactant can be provided within the capping layer, and the capping layer is placed on any useful layer or structure. The capping layer can have any useful thickness (e.g., any thickness as described herein, including about 0.1 nm to about 5 nm).

[0089] Furthermore, two or more different precursors can be used within each layer (e.g., a film or a capping layer). For example, an alloy can be formed using two or more of the metal-containing precursors of this specification. Further exemplary EUV-sensitive materials, as well as processing methods and apparatus, are described in U.S. Patent No. 9,996,004, International Publication No. 2020 / 102085, and International Publication No. 2019 / 217749, each of which is incorporated herein by reference in whole.

[0090] In block 104 of process 100, the back surface or bevel of the substrate may be optionally cleaned and / or the edge beads of the photoresist deposited in the previous step may be removed. Such cleaning or removal steps may be useful for removing particles that may be present after the photoresist layer has been deposited. The removal step may include treating the wafer with a wet metal oxide (MeOx) edge bead removal (EBR) step.

[0091] In block 106 of process 100, post-coating firing (PAB) or post-coating treatment can be optionally performed. Such treatment can improve the etching resistance of the unexposed material to aqueous or non-aqueous solutions. In one example, such treatment can increase the chemical composition difference (or contrast) between the unexposed and exposed regions, and thus the PAB operation is performed. In another example, such treatment can decrease the chemical composition difference (or contrast) between the unexposed and exposed regions, and therefore the PAB operation is not performed. In yet another example, PAB is used to remove residual moisture from the layer and form a cured resist film. PAB may include some combination of heat treatment, chemical exposure, and / or moisture to increase the EUV sensitivity of the film, thereby reducing the amount of EUV exposure required to develop a pattern in the film. In certain embodiments, the PAB step is performed at a temperature above about 100°C, or at a temperature of about 100°C to about 200°C or about 100°C to about 250°C. In other embodiments, the PAB step is performed at a temperature of about 190°C to about 350°C in the absence of an O-containing gas. In another example, post-coating treatment may involve exposing the film to an inert gas or CO2, which may optionally include cooling or heating. The use of an inert gas can provide metal-oxygen-metal species, while the use of CO2 can provide metal carbonate species within the film.

[0092] In block 108 of process 100, the film is exposed to EUV radiation to develop a pattern. Generally, EUV exposure causes a change in the chemical composition of the film, creating an etching-selective contrast that can be used to remove a portion of the film. Such a contrast can provide a positive resist. However, it will be understood that EUV exposure can alternatively cause a contrast so that unexposed areas are selectively removed. Such a contrast can provide a negative resist, as described herein. EUV exposure may include exposure having wavelengths in the range of about 10 nm to about 20 nm (e.g., about 13.5 nm in a vacuum atmosphere) in a vacuum atmosphere, for example.

[0093] In block 110 of process 100, post-exposure firing (PEB) is performed on the exposed film, thereby further removing residual moisture, promoting chemical concentration within the film, increasing the contrast of the etching selectivity of the exposed film, or post-processing the film in any useful manner. In one example, such processing can reduce the difference in chemical composition (or contrast) between the unexposed and exposed areas, and therefore no PEB operation is performed.

[0094] In block 112 of process 100, the photoresist pattern is developed by positive or negative development. In various embodiments of development, unexposed areas are selectively removed (to provide a pattern within the negative resist). These steps may be a wet process using one or more developers or developer solutions, followed by an optional rinsing operation (e.g., using deionized water or another solvent) or an optional drying operation (e.g., using air or any heat under inert conditions). In certain embodiments, the development step is a wet process applied to a tin-based film. In other embodiments, the development step is a dry process applied to a tin-based film. For example, the dry process includes a halide-containing chemical.

[0095] After block 112, a post-development inspection may be performed. If necessary, reprocessing is performed by returning to iteration 102.

[0096] In block 114 of process 100, the photoresist is treated before pattern transfer. The treatment may be heat treatment, plasma treatment, chemical treatment, selective deposition treatment, or a combination of the aforementioned treatments. Heat treatment may expose the photoresist to a high temperature of about 200°C to about 300°C to reduce defects and LWR. Plasma treatment may expose the photoresist to a plasma such as direct (in-situ) plasma or remote plasma to increase the density of the photoresist and reduce LWR. Chemical treatment may expose the photoresist to reactive chemical species such as halide species (e.g., tungsten hexafluoride) or carbon-containing precursors (e.g., carbon monoxide, metal-organic precursors) to improve etching resistance, reduce gas emission, and increase line CD. Selective deposition treatment may expose the photoresist to a chemical precursor to selectively deposit a protective coating on the photoresist to reduce DtS, improve etching resistance, reduce gas emission, and increase line CD. One or more of the aforementioned treatments are applied to the photoresist after development to improve the performance of the photoresist during pattern transfer.

[0097] In block 116 of process 100, one or more substrate layers are etched using a photoresist mask for pattern transfer. Such substrate layers are located beneath the photoresist mask and may be removable by lithographic etching. Pattern transfer etching can etch the material to a desired depth to form multiple patterned features. In some embodiments, one or more substrate layers are amorphous carbon (aC), amorphous silicon (a-Si), tin oxide (e.g., SnO x ), silicon oxide (e.g., SiO2), silicon oxynitride (e.g., SiO2) x N y ), silicon carbide (for example, SiO x C y), silicon nitride (e.g., Si3N4), titanium oxide (e.g., TiO2), titanium nitride (e.g., TiN), tungsten (e.g., W), doped carbon (e.g., W-doped C), tungsten oxide (e.g., WO x This may include ), hafnium oxide (e.g., HfO2), zirconium oxide (e.g., ZrO2), and aluminum oxide (e.g., Al2O3). Defects or variations in the CD within the photoresist mask are replicated within the patterned material during pattern transfer etching. Furthermore, insufficient etching resistance negatively affects the transfer of the pattern to the underlying substrate layer throughout the etching process. Post-development treatment of the photoresist mask mitigates the aforementioned problems to ensure successful pattern transfer during pattern transfer etching.

[0098] After pattern transfer, post-etching inspection may be performed. If necessary, rework is carried out by returning to iteration 102.

[0099] Figures 2A and 2C show schematic cross-sectional views providing an overview of various processing stages, including the development and processing of the photoresist. As shown in Figure 2A, the wafer 200 includes a substrate 202 and a substrate layer 204 to be etched. The patterning structure can include any useful substrate. For example, the incoming wafer can be prepared with a substrate surface of the desired material, and the top layer of material is the layer on which the resist pattern is transferred. Material selection may vary depending on the integration density, but generally, it is desirable to select a material that can be etched with high selectivity (i.e., at a much faster rate than those) to the EUV resist or imaging layer.

[0100] In some embodiments, the substrate is a hard mask used for lithographic etching of the underlying semiconductor material. The hard mask is amorphous carbon (aC), silicon oxide (e.g., SiO2), and SiO2. x ), silicon oxynitride (for example, SiO x N y ), silicon carbide (for example, SiO x Cy ), silicon nitride (e.g., Si3N4), titanium oxide (e.g., TiO2), titanium nitride (e.g., TiN), tungsten (e.g., W), doped carbon (e.g., W-doped C), tungsten oxide (e.g., WO x The substrate material may include any of the following materials: ), hafnium oxide (e.g., HfO2), zirconium oxide (e.g., ZrO2), and aluminum oxide (e.g., Al2O3). Suitable substrate materials include various carbon-based films (e.g., ashingable hard masks (AHMs)), silicon-based films (e.g., SiO2O3). x SiC x SiO x C y SiO x N y SiO x C y N z The layers may include a-Si:H, poly-Si, or SiN, or any other (generally sacrificial) film applied to facilitate the patterning process. In various embodiments, the layers may be 1 nm to 100 nm thick, or 2 nm to 10 nm thick.

[0101] In some embodiments, the substrate layer 204 includes an ashingable hard mask such as CVD amorphous carbon spin-on carbon or other materials (e.g., silicon, silicon oxide, silicon nitride, silicon carbide, etc.). In some embodiments, the substrate layer 204 may be a layer stack disposed on the substrate 202. The wafer 200 further includes a photopatterned metal-containing EUV resist film 206. For example, the photopatterned metal-containing EUV resist film 206 may be an organometallic layer disposed on the substrate layer 204 to be etched. The photopatterned metal-containing EUV resist film 206 may have a thickness of about 5 nm to about 50 nm or about 10 nm to about 30 nm. The photopatterned metal-containing EUV resist film 206 may be provided in a process chamber after photopatterning in an EUV scanner and / or after PEB processing. The photopatterned metal-containing EUV resist film 206 includes a non-EUV exposure region 206a and an EUV exposure region 206b.

[0102] As shown in Figure 2B, in the development process, the non-EUV exposed regions 206a of the photopatterned metal-containing EUV resist film 206 are removed. Development may be performed using a wet or dry developer. When a dry developer is applied, dry development may proceed with or without plasma generation. In some implementations, the dry developer may contain a hydrogen halide-containing chemical. The removal of the non-EUV exposed regions 206a forms a photoresist mask of the photopatterned metal-containing EUV resist film 206 after development.

[0103] As shown in Figure 2C, the substrate layer 204 is etched using a photoresist mask 208 to form concave features defined by the photoresist mask 208 within the wafer 200. The wafer 200 undergoes pattern transfer etching to selectively remove the substrate layer 204 with respect to the chemically modified photoresist mask 208. Pattern transfer etching can be performed using dry etching or wet etching. For example, dry etching may utilize a fluorine-based plasma etching process or an oxygen-based plasma etching process. Pattern transfer etching can etch through the substrate layer 204 according to the pattern defined by the photoresist mask 208. In some embodiments, the photoresist mask 208 preserves, or at least substantially preserves, the increased line CD after pattern transfer etching.

[0104] Method for recovering hydrogen halogens for dry developing Referring to Figures 1 and 2A-2C, the conventional methods described above can be made more efficient in both pre-development (how much reagent is supplied to the process chamber) and post-development (how excess reagent is managed after the wafer has been etched) by focusing on the hydrogen halide reagent used in dry development. The vapor phase hydrogen halide dry development of metal oxide photoresist can be expressed by the following formula when the hydrogen halide is HBr and the metal oxide photoresist is an organotin oxide.

[0105] HBr (excess) + [alkyl-Sn(O)OH] n →Alkyl-SnBr3+H2O (Equation 1)

[0106] A large excess of halide is used to propel the reaction on the right-hand side of the equation. HBr is conventionally supplied continuously into the process chamber in quantities hundreds of times the required stoichiometric amount. The halide is typically flowed into the process chamber with an inert gas at a flow rate of approximately 300 sccm to 2,000 sccm for 30 seconds to 1 minute or more. The use of such a large excess of halide is expensive and, in some situations, can lead to equipment corrosion. As a result, corrosion can cause system downtime for cleaning and / or replacing corroded parts. Therefore, a more efficient dry developing process is desirable.

[0107] To improve the dry developing process, the methods described herein focus on 1) reducing the amount of hydrogen halide used and / or 2) efficiently managing excess hydrogen halide. Techniques for efficient management include, but are not limited to, i) purifying in situ and returning excess hydrogen halide to the process chamber for recycling; ii) capturing hydrogen halide in a separate process and optionally purifying it; or iii) neutralizing hydrogen halide with an alkaline spray abatement module and optionally reconstituting the neutralized hydrogen halide for reuse, as described in the following paragraphs.

[0108] In certain embodiments, to avoid excess hydrogen halides generated from the supply of a continuous flow to the process chamber, a static amount of hydrogen halides is utilized that is limited to up to 50 times the stoichiometric amount required to decompose the EUV-unexposed portions of the photopatterned metal oxide EUV resist into water and volatile metal halides.

[0109] The static volume can be delivered in a duration of approximately 1 to 60 seconds, 5 to 10 seconds, 5 to 15 seconds, or less than 15 seconds. The static volume is supplied to the process chamber at a flow rate of approximately 1 sccm to 100 sccm, 10 sccm to 75 sccm, or 25 to 50 sccm. After the static volume is delivered, the photopatterned metal oxide EUV resist is immersed in the hydrogen halide volume for approximately 1 to 60 seconds, 5 to 45 seconds, or 10 to 40 seconds.

[0110] In some embodiments, the donated amount may be less than 50 times the stoichiometric amount of hydrogen halide, less than 10 times the stoichiometric amount of hydrogen halide, about 2 to about 10 times the stoichiometric amount of halide, or about 3 to about 7 times the stoichiometric amount of halide, or about 4 to about 6 times the stoichiometric amount of halide. In some embodiments, the partial pressure of HBr may be adjusted to further optimize the process.

[0111] Figure 3A shows scanning electron microscope (SEM) images of exemplary photoresists after dry development with hydrogen bromide by the method in a particular disclosed embodiment. They were formed by co-flowing 200 sccm of HBr and N2 in a processing chamber containing organotin oxide photoresist for 15 seconds until the chamber pressure reached 3.8 Torr, at which point the system was isolated from all introduced gases and vacuum systems. The coupons were then immersed in the HBr / N2-filled chamber at approximately 30°C for 40 seconds. At the end of the immersion step, the chamber was pumped down before removing the coupons, and the resulting patterns were subsequently imaged using a CD SEM. The following images show a clean, dense line / space array with a roughness of less than 3.1 nm, as well as open areas showing no residue.

[0112] Figure 3B shows scanning electron microscope (SEM) images of a photoresist after dry development with trimethylsilyl chloride according to a particular disclosed embodiment. A stoichiometric calculation of a suitable amount of trimethylsilyl chloride for use in the method described herein can be based on the following formula in a particular embodiment.

[0113] [alkyl-Sn(O)OH] n +3n Me3SiCl→n alkylSnCl3+3n / 2(SiMe3)2O (Equation 2)

[0114] The example was formed by placing 0.2 mL of (CH3)3SiCl and EUV-patterned organotin oxide photoresist, contained in a small vial, into a nitrogen-purged 100 mL sealed bottle. The exposure time of the photoresist to TMS-Cl vapor ranged from 10 to 30 minutes. The vapor pressure of (CH3)3SiCl in the bottle was assumed to be 100 Torr, which is the known vapor pressure of (CH3)3SiCl at room temperature. At the end of the immersion step, the photoresist was removed from the bottle and pumped down for 5 minutes in a vacuum transfer chamber in a glove box. The resulting pattern was then imaged using a CD SEM. The following images show dense line / space arrays with line widths and space widths controlled by exposure time, as well as open areas showing no residue after 30 minutes of exposure. The P30 line / space pattern in the organotin oxide photoresist is 45 mJ / cm². 2 It was produced with EUV exposure. After EUV exposure, the photoresist was fired in air at 180°C for 4 minutes, and then in 9 Torr N2 at 195°C for 3 minutes.

[0115] The results above demonstrate that line / space patterns can be observed after a simple static dry development process. The amount of etching agent used in the experiment was the stoichiometric amount required to etch away the unexposed photoresist, plus the additional partial pressure of the etching agent in the bottle volume. The amount of etching agent required to run continuously for 30 minutes should naturally be greater than the amount used in the experiment. Conditions were limited by the experimental apparatus and depended on the laboratory temperature, bottle volume, and the vapor pressure of trimethylsilyl chloride. Reaction time was used to control the development process. Additional process conditions can be modified in mass production processes.

[0116] In certain embodiments, this small-scale example can be transferred to a larger process chamber where process conditions (pressure, temperature, and time) for dry development can be optimized for mass production. The photoresist is placed in a vacuum chamber and pumped down to the base pressure, followed by closing the chamber isolation valve. A flow of about 100 sccm to about 2,000 sccm containing trimethylsilyl chloride or trimethylsilyl bromide is then used to fill the chamber volume to a determined pressure, such as about 100 mTorr to about 500 mTorr, or up to 2 Torr in certain embodiments. A parallel flow of an inert gas such as argon, nitrogen, or helium at a rate of about 100 sccm to about 2,000 sccm can be used to dilute the etching agent to a determined partial pressure, such as about 5% to about 90% of the total chamber pressure, to help reach the desired chamber pressure. The photoresist is immersed in a chamber for a set time, such as approximately 20 to 300 seconds, while being exposed to trimethylsilyl chloride or trimethylsilyl bromide vapor, after which the chamber is evacuated and purged to remove etching byproducts. The temperature of the photoresist during immersion is controlled by placing the photoresist wafer on a pedestal that is heated or cooled in a temperature range of approximately -20°C to approximately 75°C. Furthermore, the temperature of the container holding the trimethylsilyl chloride or trimethylsilyl bromide reservoir can be heated to 35°C to 100°C to sufficiently increase the vapor pressure and vaporization rate of the etching agent, thereby reducing the time required to fill the process chamber with the desired partial pressure of the etching agent.

[0117] A method for recycling hydrogen halides used in a dry developing process is another technique for effectively managing and controlling the amount of hydrogen halides used by recirculating excess hydrogen halides, purifying them in situ, and returning them to the process chamber. During dry developing, an effluent process stream can be generated containing volatile byproducts such as organometallic halides, water, and metal halides, as well as a large excess of hydrogen halides. The organometallic halides may be, for example, isopropyltin tribromide, and the metal halides may be, for example, tin tetrabromide. These byproducts can be separated from the excess hydrogen bromide by condensation and / or absorption, and the purified hydrogen bromide can then be recirculated back into the process chamber for reuse, as shown in Figure 4A, which is described in more detail below. Beyond the advantages provided by recycling hydrogen halides, this method is also useful because the removal of water from the process chamber can help drive the reaction shown in Equation 1 to the right, thus reducing the amount of hydrogen halides required.

[0118] Furthermore, this method can be used in conjunction with the method described above, in which only a specific amount of HBr is supplied to the process chamber.

[0119] One alternative method for efficiently utilizing halides in the dry developing process is to capture the halides and then recover them by an optional separate process of purification. Excess halides can be recovered downstream of the vacuum pump by condensation in a pressure-compatible collection container in a low-temperature condenser, as shown in Figure 4B, which will be described in more detail below. Optionally, less volatile by-products (e.g., water and isopropyl-SnBr3) may be removed by a trap positioned between the vacuum pump and the condenser. When the pressure-compatible collection container is full, it can be sealed and processed elsewhere (either in-house or off-site at a chemical vendor / partner). In some embodiments, off-site purification may be performed by returning impure hydrogen halides to the supplier.

[0120] A second alternative method for indirectly recovering hydrogen halides used in dry developing is to neutralize excess halides with an alkaline spray abatement system. In one embodiment, an alkaline solution, such as a lime solution, is sprayed onto the process gas effluent (exhaust from a vacuum pump) that converts halides such as HBr into CaBr2 and water. Optionally, the HBr can then be reconstituted for reuse, for example, by treating CaBr2 with H2SO4 to form CaSO4 and HBr. A suitable apparatus is shown in Figure 5 and described in more detail below.

[0121] Furthermore, this method can be used in conjunction with the method described above, in which only a specific exposure amount of HBr is supplied to the process chamber, in order to capture any remaining excess hydrogen halide that would still be present in the vacuum pump exhaust.

[0122] Device Figure 4A is a schematic diagram of an exemplary system 400 for recycling hydrogen halides from dry developer in a process chamber and upstream of a vacuum pump, according to a particular disclosed embodiment.

[0123] The schematic diagram relates to a system 400 comprising a process chamber 401 having an HBr inlet valve 415, an air agitation module 406 for circulating process gas 408, two identical condensers 402 and 403, and a recirculation conduit 407. Condensers 402 and 403 can be used alternatively to remove etching byproducts (H2O, i-PrSnBr3, SnBr4) from process gas 408 containing excess HBr. Process gas 408 may be transported from process chamber 401 through conduit 409 when valve 412b, which is a gas recirculation inlet, is open. Condensers 402 and 403 include an inner water-absorbing liner material 404 and an outer temperature-adjustable jacket 405a and 405b.

[0124] The inner water-absorbing liner material 404 captures water. Suitable adsorbents for the liner material are selective materials for adsorbing / removing H2O vapor and remaining relatively inert to HBr or HCl. Examples include, but are not limited to, anhydrous aluminum oxide, silica gel, and / or various aluminosilicates and molecular sieve formulations for dehydration applications. Suitable methods and materials include those described in U.S. Patent No. 4,853,148 in certain embodiments.

[0125] Condenser 402 includes a temperature-adjustable jacket 405a, and condenser 403 includes a temperature-adjustable jacket 405b. When condenser 402 is in use, the temperature-adjustable jacket 405a is operated in cooling mode to condense HBr. Condenser 402 is in use when valves 412a and 412b are open, while valve 416 is closed.

[0126] As the process gas flows into the condenser 402, water, organotin Br3, and SnBr4 are removed, while the purified HBr is then recirculated back into the process chamber, where selective etching of the unexposed resist material can continue. This recycled HBr flows through the open valve 412a and the recirculation conduit 404, and returns to the process chamber through the inlet 411.

[0127] When condenser 402 is in use, condenser 403 can be cleaned. To clean condenser 403, the temperature-adjustable jacket 405b operates in heating mode to remove contaminants or residual by-products. While valves 413a and 413b are closed, valve 417 is open, allowing volatile contaminants to be removed from condenser 403.

[0128] Conversely, while condenser 402 is being cleaned, condenser 403 can be used for recycling. In this way, the system can operate continuously without the need to stop dry developing for cleaning. When condenser 403 is in use, the temperature-adjustable jacket 405b is operated in cooling mode to capture impurities. Condenser 403 is in use when valves 413a and 413b are open, while valve 417 is closed.

[0129] When condenser 403 is in use, condenser 402 can be cleaned. To clean condenser 402, the temperature-adjustable jacket 405a operates in heating mode to remove contaminants or residual by-products. While valves 412a and 412b are closed, valve 416 is open, allowing volatile contaminants to be removed from condenser 402.

[0130] During recycling and / or cleaning operations, valve 414 is closed. When valve 414 is opened, process gas flows from the process chamber to the vacuum pump.

[0131] A system with two condensers is shown, but in other embodiments, four condensers may be used.

[0132] System 400 can be integrated with the process chamber or tools shown in Figures 6 to 9 and may be associated with a main controller or auxiliary controller configured to perform the hydrogen halide reagent recycling technology described herein.

[0133] Figure 4B is a schematic diagram of an exemplary system 450 for recovering hydrogen halides from dry development in a process chamber and downstream of a vacuum pump, according to a particular disclosed embodiment.

[0134] System 450 is configured downstream of a process chamber (not shown) and a vacuum pump 455. The vacuum pump 455 receives effluent from the process chamber via a channel 460, which may contain various by-products and hydrogen halides such as HBr. The exhaust from the vacuum pump is supplied to a cryogenic condenser 480 via channels 465 and 475. A suitable temperature may be about -80°C or below. Optionally, a trap 470 may be placed between the vacuum pump 455 and the condenser 480 to capture volatile metal halide by-products. The trap 470 may be cooled below ambient temperature to enhance the capture of undesirable by-products.

[0135] The condenser 480 is equipped with a pressure-compatible collection container for holding the condensed impure hydrogen halide 485. When the container is full, it can be removed off-site, for example, by a chemical company, for further purification.

[0136] Flow path 490 is for draining any remaining gas or vapor from the system.

[0137] System 450 can be integrated with the process chamber or tool shown in Figures 6 to 9 and may be associated with a main controller or auxiliary controller configured to perform the recovery techniques described herein.

[0138] Figure 5 is a schematic diagram of an exemplary system 500 for processing by-products from dry development in a process chamber and downstream of a vacuum pump, according to a particular disclosed embodiment. Process gas 501 from dry development, containing by-products and excess hydrogen halide reagents, is transported out of the process chamber via a vacuum pump 502. The exhaust from the vacuum pump flows through a conduit 503 to a toxication module 504, where an alkaline aqueous solution 505, such as a CaO / Ca(OH)2 solution, is sprayed onto it. The spray neutralizes hydrogen halides (such as HBr) and other volatile by-products, which are collected in the toxication module 504 as a neutralized solution 505, which in some embodiments may contain CaBr2, while the washed exhaust 507 is discharged from the toxication module. The neutralized solution can be further processed and converted into a usable hydrogen halide reagent, for example, by treating CaBr2 with H2SO4 to obtain HBr.

[0139] System 500 can be integrated with the process chamber or tool shown in Figures 6 to 9 and may be associated with a main controller or auxiliary controller configured to perform the neutralization techniques described herein.

[0140] Furthermore, the upstream system 400 can be combined with either the downstream system 450 or the downstream system 500.

[0141] The apparatus of this disclosure is configured for post-development processing of patterned metal-containing photoresist masks. The apparatus may be configured for other processing operations such as deposition, beveling and back cleaning, post-coating firing, EUV scanning, post-exposure firing, development, etching, and other operations. In some configurations, the apparatus is configured to perform a number of dry operations. In some configurations, the apparatus is configured to perform a combination of wet and dry operations. The apparatus may include a single wafer chamber or multiple stations within the same process chamber. Using multiple stations within the same process chamber, the various processing operations described herein may be performed at different stations within the same process chamber. In some embodiments, the process chamber for post-development processing of this disclosure may be the same chamber as development, the same chamber as pattern transfer etching, or the same chamber as both development and pattern transfer etching.

[0142] An apparatus configured to perform post-development processing includes a process chamber having a substrate support. The apparatus may include at least one reactive gas source in fluid communication with the process chamber. The apparatus may include one or more gas lines for delivering one or more reactive gas species. In some embodiments, one or more reactive gas species may include organic gas species, organometallic gas species, metal-containing gas species, or combinations thereof. In some embodiments, one or more reactive gas species may include oxygen-containing gases, carbon-containing gases, hydrogen-containing gases, nitrogen-containing gases, halogen-containing gases, or combinations thereof. One or more reactive gas species may be delivered to the process chamber via one or more gas lines to process the metal-containing photoresist mask after development. The apparatus may include one or more heating elements for temperature control. Such heating elements may be located within the process chamber and / or within the substrate support. Alternatively, such heating elements may be located outside the process chamber. In some configurations, the apparatus may include a plasma source for generating plasma during processing of the metal-containing photoresist mask after development. In some configurations, one or more reactive species may selectively deposit a protective film on the metal-containing photoresist mask after development. The apparatus may further include one or more sensors for detecting particle counts, wafer counts, thickness counts, or other parameters to trigger the endpoint of post-development processing.

[0143] Figure 6 shows a schematic diagram of an exemplary process station for maintaining an environment suitable for performing photoresist development and photoresist processing operations, according to several embodiments. For simplicity, process station 600 is shown as a standalone process station having a process chamber body 602 for maintaining a low-pressure environment. However, it will be understood that multiple process stations 600 may be included in a common process tool environment. Furthermore, it will be understood that in some embodiments, one or more hardware parameters of process station 600, including those described in detail below, may be programmed by one or more computer controllers.

[0144] Multiple process stations 600 may be included in a common low-pressure process tool environment. For example, Figure 7 shows an implementation of a multi-station process tool 700. In some implementations, one or more hardware parameters of the process tool 700, including those described in detail below, may be programmed by one or more computer controllers 750.

[0145] The process station may be configured as a module within a cluster tool. Figure 9 shows a semiconductor process cluster tool architecture having vacuum integrated deposition and patterning modules suitable for implementation of the configuration described herein. Such a cluster process tool architecture may include resist deposition, resist exposure (EUV scanner), resist development, resist reprocessing, and etching modules, as described above with reference to Figures 6 and 7 and further below.

[0146] Returning to Figure 6, the process station 600 is in fluid communication with the reactant delivery system 601 to deliver the process gas to the showerhead 606. The reactant delivery system 601 optionally includes a mixing vessel 604 for mixing and / or adjusting the process gas for delivery to the showerhead 606. One or more mixing vessel inlet valves 620 may control the introduction of the process gas into the mixing vessel 604. If plasma exposure is used, the plasma may be delivered to the showerhead 606 or generated within the process station 600. As described above, non-plasma thermal exposure is preferred in at least some implementations.

[0147] Figure 6 includes an optional vaporization point 603 for vaporizing the liquid reactants supplied to the mixing vessel 604. In some implementations, a liquid flow controller (LFC) may be provided upstream of the vaporization point 603 to control the mass flow rate of the liquid for vaporization and delivery to the process station 600. For example, the LFC may include a thermal mass flow meter (MFM) located downstream of the LFC. The plunger valve of the LFC may then be adjusted in response to a feedback control signal provided by a proportional-integral-derivative (PID) controller electrically connected to the MFM.

[0148] The showerhead 606 distributes the process gas toward the substrate 612. In the mounting configuration shown in Figure 6, the substrate 612 is located below the showerhead 606 and is shown resting on the pedestal 608. The showerhead 606 may have any suitable shape and may have any suitable number and arrangement of ports for distributing the process gas toward the substrate 612.

[0149] In some implementations, the pedestal 608 may be raised or lowered to expose the substrate 612 to the volume 607 between the substrate 612 and the showerhead 606. In some implementations, the height of the pedestal may be programmed to adjust by a suitable computer controller. In some implementations, the showerhead 606 may have multiple plenum volumes with multiple temperature controls.

[0150] In some implementations, the pedestal 608 may be temperature-controlled via a heater 610. In some implementations, the pedestal 608 may be heated during post-development processing to a temperature above 0°C up to 300°C, for example, 50°C to 280°C, or for example, about 100°C to 240°C, as described in the disclosed implementations. In some implementations, the heater 610 of the pedestal 608 may include a plurality of independently controllable temperature control zones.

[0151] Furthermore, in some implementations, pressure control of the process station 600 may be provided by a butterfly valve 618. As shown in the implementation in Figure 6, the butterfly valve 618 throttles the vacuum provided by a downstream vacuum pump (not shown). However, in some implementations, pressure control of the process station 600 may also be adjusted by changing the flow rate of one or more gases introduced into the process station 600.

[0152] In some implementations, the position of the showerhead 606 may be adjusted relative to the pedestal 608 to change the volume between the substrate 612 and the showerhead 606. Furthermore, it will be understood that the vertical position of the pedestal 608 and / or the showerhead 606 may be varied by any suitable mechanism within the scope of this disclosure. In some implementations, the pedestal 608 may include a pivot axis for rotating the orientation of the substrate 612. In some implementations, it will be understood that one or more of these exemplary adjustments may be performed programmatically by one or more suitable computer controllers.

[0153] For example, if plasma may be used in a descamming, processing, deposition, or smoothing operation, the showerhead 606 and pedestal 608 are electrically connected to a radio frequency (RF) power supply 614 and a matching network 616 for powering the plasma. In some implementations, the plasma energy may be controlled by controlling one or more of the process station pressure, gas concentration, RF source power, RF source frequency, and plasma power pulse timing. For example, the RF power supply 614 and the matching network 616 may operate at any suitable power to form a plasma having a desired composition of radical species. An example of a suitable power is up to about 1000W.

[0154] In some implementations, instructions to a computer controller (not shown) may be provided via input / output control (IOC) sequencing instructions. For example, instructions for setting the conditions of a process stage may be included in the corresponding recipe stage of a process recipe. In some cases, process recipe stages may be arranged sequentially so that all instructions for a process stage are executed simultaneously with that process stage. In some implementations, instructions for setting one or more reactor parameters may be included in the recipe stage. For example, the recipe stage may include instructions for setting the flow rate of an etching gas, such as hydrogen halide, and a time delay instruction for the recipe stage. In some implementations, the controller may include any of the features described below with respect to the controller 750 in Figure 7.

[0155] The process chamber may also include a UV exposure module (not shown).

[0156] In some embodiments, the process chamber may also include a photoresist thickness sensor module (not shown). The photoresist thickness sensor module may be a spectrophotometer comprising a lamp source, an optical cable, and a spectrometer system operating in a spectral range of about 200 to about 900 nm. The reflectometer can be useful for monitoring the thickness of the photoresist during dry development, as it measures the wafer reflectance in situ over time.

[0157] As described above, one or more process stations may be included in a multi-station process tool. Figure 7 shows a schematic diagram of an implementation of a multi-station process tool 700 having an inbound load lock 702 and an outbound load lock 704, one or both of which may include a remote plasma source. A robot 706 at atmospheric pressure is configured to move a wafer from a cassette loaded through a pod 708 to the inbound load lock 702 via an atmospheric port 710. The wafer is placed by the robot 706 on a pedestal 712 in the inbound load lock 702, the atmospheric port 710 is closed, and the load lock is pumped down. If the inbound load lock 702 includes a remote plasma source, the wafer may be exposed to remote plasma processing to process the substrate surface in the load lock before being introduced into the processing chamber 714. Furthermore, the wafer may also be heated in the inbound load lock 702, for example, to remove moisture and adsorbed gases. Next, the chamber transport port 716 to the processing chamber 714 is opened, and another robot (not shown) places the wafer into the reactor on the pedestal of the first station, which is located inside the reactor for processing. The configuration shown in Figure 7 includes a load lock, but it will be understood that in some configurations, direct entry of the wafer into the process station may be provided.

[0158] The illustrated processing chamber 714 includes four process stations numbered 1 to 4 in the implementation shown in Figure 7. Each station has a heated pedestal (station 1 is shown as 718) and a gas line inlet. In some implementations, it will be understood that each process station may have different or multiple purposes. For example, in some implementations, a process station may be switchable between a developing process mode and an etching process mode. Additionally or alternatively, in some implementations, the processing chamber 714 may include one or more matched pairs of developing and etching process stations. Although the illustrated processing chamber 714 includes four stations, it will be understood that the processing chamber according to this disclosure may have any appropriate number of stations. For example, in some implementations, the processing chamber may have five or more stations, and in other implementations, the processing chamber may have three or fewer stations.

[0159] Figure 7 shows an implementation of a wafer handling system 790 for transporting wafers within a processing chamber 714. In some implementations, the wafer handling system 790 may transport wafers between various process stations and / or between process stations and load locks. It will be understood that any suitable wafer handling system may be used. Non-limiting examples include wafer carousels and wafer handling robots. Figure 7 also shows an implementation of a controller 750 (e.g., a system controller) used to control the process conditions and hardware state of the process tool 700. The controller 750 may include one or more memory devices 756, one or more mass storage devices 754, and one or more processors 752. The processor 752 may include a CPU or computer, analog and / or digital input / output connections, a stepping motor controller board, etc.

[0160] In some implementations, the controller 750 controls all activities of the process tool 700. The controller 750 runs system control software 758, which is stored in a mass storage device 754, loaded into a memory device 756, and executed on the processor 752. Alternatively, the control logic may be hardcoded within the controller 750. For these purposes, application-specific integrated circuits, programmable logic devices (e.g., field-programmable gate arrays, or FPGAs) may be used. Wherever “software” or “code” is used in the following description, functionally equivalent hardcoded logic may be used instead. The system control software 758 may include instructions for controlling timing, gas mixture, gas flow rate, chamber and / or station pressure, chamber and / or station temperature, wafer temperature, target power level, RF power level, substrate pedestal, chuck and / or susceptor position, and other parameters of a particular process performed by the process tool 700. The system control software 758 may be configured in any suitable manner. For example, various process tool component subroutines or control objects may be written to control the behavior of process tool components used to execute various process tool processes. The system control software 758 may be coded in any suitable computer-readable programming language.

[0161] In some implementations, the system control software 758 may include input / output control (IOC) sequencing instructions for controlling the various parameters described above. In some implementations, other computer software and / or programs may be used, stored in the mass storage device 754 and / or memory device 756 associated with the controller 750. Examples of such programs or sections of programs include a substrate positioning program, a process gas control program, a pressure control program, a heater control program, and a plasma control program.

[0162] The substrate positioning program may include program code for process tool components used to load the substrate onto the pedestal 718 and control the spacing between the substrate and other parts of the process tool 700.

[0163] The process gas control program may include code to control the process gas composition and flow rate, and optionally to include code to flow gas to one or more process stations before deposition in order to stabilize the pressure within the process stations. The pressure control program may include code to control the pressure within the process stations by adjusting, for example, throttle valves in the exhaust systems of the process stations, gas flow to the process stations, etc.

[0164] The heater control program may include code for controlling the current to the heating unit used to heat the substrate. Alternatively, the heater control program may control the delivery of a heat transfer gas (such as helium) to the substrate.

[0165] The plasma control program may include code for setting the RF power levels applied to process electrodes in one or more process stations according to the implementation described herein.

[0166] The pressure control program may include code for maintaining the pressure in the reaction chamber according to the implementation described herein.

[0167] In some implementations, there may be a user interface associated with the controller 750. The user interface may include a display screen, a graphical software display of the device and / or process conditions, and user input devices such as a pointing device, keyboard, touch screen, and microphone.

[0168] In some implementations, the parameters adjusted by the controller 750 may relate to process conditions. Non-limiting examples include the composition and flow rate of the process gas, temperature, pressure, and plasma conditions (such as RF bias power level). These parameters may be provided to the user in the form of a recipe, which may be entered using a user interface.

[0169] Signals for monitoring the process may be provided by analog and / or digital input connections to the controller 750 from various process tool sensors. Signals for controlling the process may be output to analog and digital output connections of the process tool 700. Non-limiting examples of process tool sensors that can be monitored include mass flow controllers, pressure sensors (such as pressure gauges), and thermocouples. Appropriately programmed feedback and control algorithms may be used in conjunction with data from these sensors to maintain process conditions.

[0170] The controller 750 may provide program instructions for carrying out the deposition process described above. The program instructions may control various process parameters such as DC power level, RF bias power level, pressure, and temperature. The instructions may also control parameters to operate the developing, washing, and / or etching processes in the various implementations described herein.

[0171] The controller 750 typically includes one or more memory devices and one or more processors configured to execute instructions so that the device performs the method according to the disclosed implementation. A machine-readable medium containing instructions for controlling process operation according to the disclosed implementation may be coupled to the controller 750.

[0172] In some implementations, the controller 750 is part of a system which may be part of the examples described above. Such a system may include semiconductor processing equipment which includes one or more process tools, one or more chambers, one or more platforms for processing, and / or specific processing components (such as wafer pedestals, gas flow systems, etc.). These systems may be integrated with electronics for controlling pre-processing, in-processing, and post-processing operations of semiconductor wafers or substrates. The electronics may be referred to as “controllers” which can control various components or sub-components of one or more systems. Depending on the processing conditions and / or the type of system, the controller 750 may be programmed to control any of the processes disclosed herein which include, but are not limited to, the delivery of processing gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, wafer transport and other transport tools for entering and exiting the tools, and / or load locks connected to or interfaced with a particular system.

[0173] Broadly speaking, the controller 750 can be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive and issue instructions, control operations, enable cleaning operations, enable endpoint measurement, etc. Integrated circuits may include chips in the form of firmware that store program instructions, chips defined as digital signal processors (DSPs), application-specific integrated circuits (ASICs), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). Program instructions may also be instructions communicated to the controller 750 in the form of various individual settings (or program files) that define operating parameters for performing a particular process on a semiconductor wafer or system. In some implementations, the operating parameters may be part of a recipe defined by a process engineer to achieve one or more processing steps during the processing of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0174] In some implementations, the controller 750 may be part of or coupled to a computer, which is integrated into, coupled to, or otherwise networked to the system, or a combination thereof. For example, the controller 750 may be all or part of a “cloud” or fab-host computer system, enabling remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of a processing operation, examine the history of past processing operations, examine trends or performance metrics from multiple processing operations, modify parameters of the current process, set processing steps following the current process, or start a new process. In some examples, a remote computer (e.g., a server) may provide process recipes to the system via a network that may include a local network or the internet. The remote computer may include a user interface that enables input or programming of parameters and / or settings, which are then communicated from the remote computer to the system. In some examples, the controller 750 receives instructions in the form of data specifying the parameters of each processing step performed during one or more operations. It should be understood that the parameters may be specific to the type of process being performed and the type of tool to which the controller 750 is configured to interface or control. Therefore, as described above, the controller 750 may be distributed, for example, by including one or more separate controllers that are networked together and operate toward a common purpose, such as the processes and control described herein. An example of a distributed controller for such purposes might be one or more integrated circuits on a chamber that communicate with one or more remotely located integrated circuits (such as platform-level or part of a remote computer) that are combined to control the processes on the chamber.

[0175] Exemplary systems may include, but are not limited to, plasma etching chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel edge etching chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, ALD chambers or modules, atomic layer etching (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, EUV lithography chambers (scanners) or modules, developing chambers or modules, and any other semiconductor processing systems related to or usable in the processing and / or manufacture of semiconductor wafers.

[0176] As described above, depending on one or more process steps performed by the tool, the controller 750 may communicate with one or more of the following: other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, nearby tools, tools located throughout the factory, a main computer, another controller, or tools used for material transport to carry wafer containers to and from tool locations and / or load ports in the semiconductor manufacturing plant.

[0177] Here, we describe ICP reactors that are suitable for etching operations in certain implementation configurations. While ICP reactors are described herein, it should be understood that capacitively coupled plasma reactors may also be used in some implementation configurations.

[0178] Figure 8 schematically shows a cross-sectional view of an inductively coupled plasma apparatus 800 suitable for performing a specific configuration or embodiment of a configuration, such as dry development, post-development processing, and / or etching. In other configurations, other tools or tool types having the capability to perform the dry development, post-development processing, and / or etching processes described herein may be used in practice.

[0179] The inductively coupled plasma apparatus 800 includes an entire process chamber 824 structurally defined by a chamber wall 801 and a window 811. The chamber wall 801 may be made of stainless steel, aluminum, or plastic. The window 811 may be made of quartz or other dielectric material. An optional internal plasma grid 850 divides the entire process chamber into an upper sub-chamber 802 and a lower sub-chamber 803. In most implementations, the plasma grid 850 may be removed, thereby utilizing the chamber space consisting of sub-chambers 802 and 803. A chuck 817 is positioned near the bottom inner surface of the lower sub-chamber 803. The chuck 817 is configured to receive and hold a semiconductor wafer 819 on which etching and deposition processes are performed. The chuck 817 may be an electrostatic chuck for supporting the wafer 819, if present. In some implementations, an edge ring (not shown) surrounds the chuck 817, and if present on the chuck 817, its upper surface is substantially planar with the top surface of the wafer 819. The chuck 817 also includes electrostatic electrodes for securing and releasing the wafer 819 from the chuck. For this purpose, a filter and a DC clamp power supply (not shown) may be provided. Other control systems may also be provided for lifting the wafer 819 from the chuck 817. The chuck 817 is rechargeable using an RF power supply 823. The RF power supply 823 is connected to a matching circuit 821 via a connector 827. The matching circuit 821 is connected to the chuck 817 via a connector 825. In this way, the RF power supply 823 is connected to the chuck 817. In various implementations, the bias voltage of the electrostatic chuck may be set to about 50V, or to different bias powers depending on the process performed according to the disclosed implementation. For example, the bias voltage may be approximately 20V to 100V, or approximately 30V to 150V.

[0180] The elements for plasma generation include a coil 833 positioned above the window 811. In some implementations, the coil is not used in the disclosed implementation. The coil 833 is manufactured from a conductive material and includes at least one complete turn. An example of the coil 833 shown in Figure 8 includes three turns. The cross-section of the coil 833 is indicated by symbols, where coils with "X" extend in the rotational direction so as to enter the page, and coils with "●" extend in the rotational direction so as to exit the page. The elements for plasma generation also include an RF power supply 841 configured to supply RF power to the coil 833. Generally, the RF power supply 841 is connected to a matching circuit 839 via a connector 845. The matching circuit 839 is connected to the coil 833 via a connector 843. In this way, the RF power supply 841 is connected to the coil 833. An optional Faraday shield 849 is positioned between the coil 833 and the window 811. The Faraday shield 849 may be maintained in a spaced relationship with respect to the coil 833. In some implementations, the Faraday shield 849 is positioned directly above the window 811. In some implementations, the Faraday shield 849 is located between the window 811 and the chuck 817. In some implementations, the Faraday shield 849 is not maintained in a spaced relationship with respect to the coil 833. For example, the Faraday shield 849 may be positioned directly below the window 811 without any gap. The coil 833, the Faraday shield 849, and the window 811 are configured to be substantially parallel to each other. The Faraday shield 849 may prevent metal or other types of material from accumulating on the window 811 of the process chamber 824.

[0181] The process gas may enter the process chamber through one or more main gas inlets 860 located in the upper sub-chamber 802 and / or through one or more side gas inlets 870. Similarly, although not explicitly shown, process gas may be supplied to the capacitively coupled plasma processing chamber using similar gas inlets. A vacuum pump, e.g., a single or two-stage mechanical dry pump and / or turbomolecular pump 840, may be used to draw process gas from the process chamber 824 and maintain the pressure within the process chamber 824. For example, the vacuum pump may be used to evacuate the lower sub-chamber 803 during a purge operation. A valve-controlled conduit may be used to fluidly connect the vacuum pump to the process chamber 824 to selectively control the application of the vacuum environment provided by the vacuum pump. This may be done using a closed-loop controlled flow limiting device, such as a throttle valve (not shown) or a pendulum valve (not shown), during plasma processing in operation. Similarly, a vacuum pump and valve-controlled fluid connection to the capacitively coupled plasma processing chamber may also be used. The wide range of pressures that need to be controlled within the process chamber for a combination of dry developing and etching can be achieved by adjusting the flow of process gases using a variable-speed vacuum system, a throttle valve, or by using two pressure regulation systems.

[0182] During the operation of the apparatus 800, one or more process gases may be supplied through the gas inlets 860 and / or 870. In certain implementations, the process gas may be supplied only through the main gas inlet 860 or only through the side gas inlet 870. In some cases, the gas inlets shown in the figure may be replaced, for example, with more complex gas inlets, one or more showerheads. The Faraday shield 849 and / or optional grid 850 may include internal channels and holes that allow for the delivery of process gases to the process chamber 824. Either or both of the Faraday shield 849 and the optional grid 850 may function as showerheads for delivering process gases. In some implementations, a liquid vaporization and delivery system may be located upstream of the process chamber 824 so that, once the liquid reactant or precursor is vaporized, the vaporized reactant or precursor is introduced into the process chamber 824 through the gas inlets 860 and / or 870.

[0183] High-frequency power is supplied to coil 833 from the RF power supply 841, causing an RF current to flow through coil 833. The RF current flowing through coil 833 generates an electromagnetic field around it. The electromagnetic field generates an induced current in the upper sub-chamber 802. The various ions and radicals generated interact physically and chemically with wafer 819, etching the features of wafer 819 and selectively depositing layers on wafer 819.

[0184] When the plasma grid 850 is used such that both the upper sub-chamber 802 and the lower sub-chamber 803 are present, the induced current acts on the gas present in the upper sub-chamber 802, generating an electron-ion plasma within the upper sub-chamber 802. An optional internal plasma grid 850 limits the amount of hot electrons in the lower sub-chamber 803. In some implementations, the apparatus 800 is designed and operated such that the plasma present in the lower sub-chamber 803 is an ion-ion plasma.

[0185] Both the upper electron-ion plasma and the lower ion-ion plasma may contain positive and negative ions, but the ratio of negative ions to positive ions will be higher in the ionic plasma. Volatile etching and / or deposition byproducts may be removed from the lower sub-chamber 803 via port 822. The chuck 817 disclosed herein may operate at high temperatures ranging from about 10°C to about 250°C. The temperature depends on the process operation and the specific recipe.

[0186] The apparatus 800 may be coupled to a facility (not shown) when installed in a cleanroom or processing facility. The equipment includes piping that provides processing gas, vacuum, temperature control, and environmental particle control. These facilities are coupled to the apparatus 800 when installed in the target processing facility. Furthermore, the apparatus 800 may be coupled to a transport chamber that allows a robot to load and unload semiconductor wafers into the apparatus 800 using typical automation.

[0187] In some implementations, the controller 830 (which may include one or more physical or logical controllers) controls some or all of the operation of the process chamber 824. The controller 830 may include one or more memory devices and one or more processors. In some implementations, the apparatus 800 includes a switching system for controlling the flow rate and duration when the disclosed implementation is performed. In some implementations, the apparatus 800 may have a switching time of up to about 500 ms, or up to about 750 ms. The switching time may depend on the chemical properties of the flow, the selected recipe, the reactor structure, and other factors.

[0188] In some implementations, the controller 830 is part of a system that may be part of the example described above. Various embodiments of the controller 830 are described above.

[0189] EUVL patterning may be performed using any suitable tool, often referred to as a scanner. The EUVL patterning tool may be a standalone device in which the substrate enters and exits for deposition and etching, as described herein. Alternatively, as will be discussed later, the EUVL patterning tool may be a module on a larger multi-component tool.

[0190] Figure 9 shows a semiconductor process cluster tool architecture 900 having vacuum-integrated deposition, patterning, and processing modules interface with a vacuum transport module, suitable for implementing the processes described herein. The arrangement of transport modules for "transporting" wafers between multiple storage facilities and processing modules is sometimes referred to as a "cluster tool architecture" system. The deposition, patterning, and processing modules are vacuum-integrated according to the requirements of a particular process. Other modules, such as those for etching, may also be included in the cluster.

[0191] The vacuum transport module (VTM) 938 interfaces with four processing modules 920a–920d, which may be individually optimized to perform various processing processes. For example, processing modules 920a–920d may be implemented to perform deposition, evaporation, ELD, dry development, washing, etching, processing, stripping, and / or other semiconductor processes. For instance, module 920a may be an ALD reactor that can operate to perform non-plasma thermal atomic layer deposition as described herein. Module 920b may be a PECVD tool. Please note that the figures are not necessarily drawn to scale.

[0192] Airlocks 942 and 946, also known as load locks or transport modules, interface with the VTM 938 and patterning module 940. This tool architecture allows for the transport of workpieces, such as semiconductor substrates or wafers, under vacuum to prevent them from reacting before exposure. The integration of the deposition module with the lithography tool is facilitated by the fact that EUVL also requires significantly lower pressures, considering the strong light absorption of incident photons by ambient gases such as H2O and O2.

[0193] As mentioned above, this integrated architecture is merely one possible implementation of the tools for carrying out the process described. The process may also be implemented using more general standalone EUVL scanners and deposition reactors, in which case the reactors may be standalone or integrated into a cluster architecture that incorporates other tools such as etching and stripping as modules, as illustrated with reference to Figure 9, for example, although this figure does not include an integrated patterning module.

[0194] Airlock 942 may be an "outside" load lock pointing to the transport of substrates from VTM 938, which serves the deposition module 920a, to the patterning module 940, and airlock 946 may be an "inside" load lock pointing to the transport of substrates from the patterning module 940 back to VTM 938. The inside airlock 946 may also provide an external interface for tools that load and unload substrates. Each process module has facets that interface the module to VTM 938. For example, deposition process module 920a has facet 936. Inside each facet, sensors, for example sensors 1-18 as shown, are used to detect the passage of wafers 926 as they move between their respective stations. The patterning module 940 and airlocks 942 and 946 may also have additional facets and sensors not shown.

[0195] The main VTM robot 922 transports the wafer 926 between modules, including airlocks 942 and 946. In one embodiment, the robot 922 has one arm, and in another embodiment, the robot 922 has two arms, each arm having an end effector 924 for picking up and transporting wafers such as wafer 926. The front-end robot 944 is used to transport the wafer 926 from the exit-side airlock 942 to the patterning module 940, and from the patterning module 940 to the entry-side airlock 946. The front-end robot 944 may also transport the wafer 926 between the entry-side load lock and the outside of the tool for loading and unloading substrates. The entry-side airlock module 946 has the ability to match the environment between air and vacuum, so that the wafer 926 can move between these two pressure environments without being damaged.

[0196] It should be noted that EUVL tools typically operate at higher vacuum levels than deposition tools. In this case, it is desirable to increase the vacuum environment of the substrate during transport between the deposition and EUVL tools so that the substrate can be degassed before entering the patterning tool. The exit airlock 942 may provide this function by holding the transported wafer at a low pressure below the pressure inside the patterning module 940 for a certain period of time, thereby releasing off-gass, and as a result, the optics of the patterning module 940 are not contaminated by gas release from the substrate. A suitable pressure for the exit off-gas airlock is 1E-8 Torr or less.

[0197] In some implementations, the controller 950 (which may include one or more physical or logical controllers) controls some or all of the operation of the cluster tools and / or separate modules thereof. Note that the controller may be local to the cluster architecture, or it may be located outside the cluster architecture within the manufacturing floor, or remotely, and connected to the cluster architecture via a network. The controller 950 may include one or more memory devices and one or more processors. The processors may include a central processing unit (CPU) or computer, analog and / or digital input / output connections, a stepper motor controller board, and other similar components. Instructions for performing appropriate control operations are executed on the processors. These instructions may be stored in memory devices associated with the controller or provided via a network. In certain implementations, the system controller runs system control software.

[0198] The system control software may include instructions for controlling the timing of application and / or the magnitude of any aspect of tool or module operation. The system control software may be configured in any suitable way. For example, various process tool component subroutines or control objects may be written to control the operation of process tool components necessary to perform various process tool operations. The system control software may be coded in any suitable computer-readable programming language. In some implementations, the system control software includes input / output control (IOC) sequencing instructions for controlling the various parameters described above. For example, each stage of a semiconductor processing process may include one or more instructions to be executed by the controller. Instructions for setting process conditions for condensation, deposition, evaporation, patterning, and / or etching stages may be included, for example, in the corresponding recipe stage.

[0199] Apparatus for post-development processing is provided in various implementation configurations. The apparatus may include a processing chamber for patterning, processing, deposition, and etching, and a controller that includes commands for post-development processing of the patterned photoresist mask. The commands may include codes for processing the patterned metal-containing photoresist mask after development within the processing chamber. Such processing may include heat treatment, plasma treatment, chemical treatment, or selective deposition of a protective layer on the patterned metal-containing photoresist mask.

[0200] It should be noted that the computer controlling wafer movement may be local to the cluster architecture, or it may be located outside the cluster architecture within the manufacturing floor, or remotely, and connected to the cluster architecture via a network. A controller as described above with respect to any of Figures 6, 7, or 8 may be implemented with the tool shown in Figure 9.

[0201] Further implementation forms While not limiting, the above discussion focuses on dry developing chambers, and further exemplary systems may include plasma etching chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel edge etching chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etching (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing systems related to or usable in the processing and / or manufacturing of semiconductor wafers.

[0202] The apparatus and processes described herein may be used in conjunction with lithography patterning tools or processes for, for example, the fabrication or processing of semiconductor devices, displays, LEDs, photovoltaic panels, etc. Typically, but not necessarily, such apparatus and processes are used or performed together in a common processing facility. Lithography patterning of films typically includes some or all of the following steps, each step made possible with several possible tools: (1) applying photoresist onto a workpiece, i.e., a substrate, using a spin-on or spray-on tool; (2) curing the photoresist using a hot plate or furnace or a UV curing tool; (3) exposing the photoresist to visible light, UV light, or X-ray light using a tool such as a wafer stepper; (4) selectively removing the resist and thereby developing the resist for patterning using a tool such as a wet bench; (5) transferring the resist pattern to the underlying film or workpiece by using a dry or plasma-assisted etching tool; and (6) removing the resist using a tool such as an RF or microwave plasma resist stripper.

[0203] conclusion While the embodiments described above have been explained in some detail to clarify understanding, it will be clear that certain changes and modifications can be made within the scope of the appended claims. It should be noted that there are many alternative ways of implementing the processes, systems, and apparatus of this embodiment. Therefore, this embodiment should be considered illustrative and not limiting, and embodiments should not be limited to the details given herein. [Explanation of Symbols]

[0204] 100 Process, 102 Block, 104 Block, 106 Block, 108 Block, 110 Block, 112 Block, 114 Block, 116 Block, 200 Wafer, 202 Substrate, 204 Substrate Layer, 206 EUV Resist Film, 206a Non-EUV Exposure Area, 206b EUV Exposure Area, 208 Photoresist Mask, 400 System, 401 Process Chamber, 402 Condenser, 403 Condenser, 404 Inner Water-Absorbing Liner Material, 405a Temperature-Adjustable Jacket, 405b Temperature-Adjustable Jacket, 406 Air Stirring Module, 407 Recirculation Conduit, 408 Process Gas, 409 Conduit, 411 Inlet, 412a Valve, 412b Valve, 413a Valve, 413b Valve, 414 Valve, 415 HBr inlet valve, 416 valve, 417 valve, 450 system, 455 vacuum pump, 460 flow path, 465 flow path, 470 trap, 475 flow path, 480 condenser, 485 hydrogen halide, 490 flow path, 500 system, 501 process gas, 502 vacuum pump, 503 conduit, 504 abatement module, 505 alkaline aqueous solution, 506 neutralized solution, 507 cleaned exhaust, 600 process station, 601 reactant delivery system, 602 process chamber body, 603 vaporization point, 604 mixing vessel, 606 shower head, 607 volume, 608 pedestal, 610 heater, 612 substrate, 614 power supply, 616 matching network, 618 butterfly valve, 620 mixing vessel inlet valve, 700 process tools, 702 Inbound load lock, 704 Outbound load lock, 706 Robot, 708 Pod, 710 Atmospheric port, 712 Pedestal, 714 Processing chamber, 716 Chamber transport port, 750 Controller, 752 Processor, 754 Mass storage device, 756 Memory device, 758 System control software, 790 Wafer handling system, 800 Inductively coupled plasma apparatus, 801 Chamber wall, 802 Upper sub-chamber, 803 Lower sub-chamber, 811 Window, 817 Chuck, 819 Semiconductor wafer, 821 Matching circuit, 822 Port, 823 RF power supply, 824 Process chamber, 825 Connection, 827830 Connector, 833 Controller, 839 Coil, 839 Matching Circuit, 840 Vacuum Pump, 841 RF Power Supply, 843 Connector, 845 Connector, 849 Faraday Shield, 850 Plasma Grid, 860 Gas Inlet, 870 Gas Inlet, 900 Semiconductor Process Cluster Tool Architecture, 920a Processing Module, 920b Processing Module, 920c Processing Module, 920d Processing Module, 922 Robot, 924 End Effector, 926 Wafer, 936 Facet, 938 Vacuum Transport Module, 940 Patterning Module, 942 Airlock, 944 Front-End Robot, 946 Airlock, 950 Controller

Claims

1. a) Providing a photopatterned metal oxide EUV resist on a substrate layer of a semiconductor substrate in a process chamber, wherein the photopatterned metal oxide EUV resist includes EUV-exposed portions and EUV-unexposed portions. b) A step of calculating the stoichiometric amount of a halogen-containing etching agent for decomposing the EUV-unexposed portion of the photopatterned metal oxide EUV resist into water and volatile metal halide, c) Dry developing the photopatterned metal oxide EUV resist by selectively removing the EUV-unexposed portions of the photopatterned metal oxide EUV resist by exposure to a certain amount of the halogen-containing etching agent to form a resist hard mask from the EUV-exposed portions; Includes, The amount of the halogen-containing etching agent includes less than 50 times the stoichiometric amount calculated in step b), Step c) is a plasma-free thermal process. A method for dry developing semiconductor substrates.

2. The method according to claim 1, wherein the amount of the halogen-containing etching agent is less than 10 times the stoichiometric amount.

3. The method according to claim 1, wherein the amount of the halogen-containing etching agent in step c) is supplied at a rate of about 300 sccm to about 2,000 sccm for about 1 to 15 seconds.

4. The method according to claim 3, further comprising the step of immersing the photopatterned metal oxide EUV resist in the amount of the halogen-containing etching agent for about 1 second to about 120 seconds.

5. The method according to claim 1, wherein the process chamber comprises a pedestal, side walls, and a shower head.

6. The method according to claim 5, wherein the side wall and the shower head are maintained at a first temperature, and the pedestal is maintained at a second temperature, the first temperature being higher than the second temperature.

7. The method according to claim 1, wherein the photopatterned metal oxide EUV resist comprises an organotin oxide.

8. The method according to claim 1, wherein the halogen-containing etching agent is hydrogen halide.

9. The method according to claim 8, wherein the hydrogen halogen is hydrogen bromide or hydrogen chloride.

10. The method according to claim 1, wherein the halogen-containing etching agent is trimethylsilyl chloride or trimethylsilyl bromide.

11. a) Providing a photopatterned metal oxide EUV resist on a substrate layer of a semiconductor substrate in a process chamber, wherein the photopatterned metal oxide EUV resist includes EUV-exposed portions and EUV-unexposed portions. b) The photopatterned metal oxide EUV resist is dry-developed by selectively removing the EUV-unexposed portions of the photopatterned metal oxide EUV resist by exposure to a halogen-containing etchant, thereby forming a resist hard mask from the EUV-exposed portions, which generates volatile byproducts and excess halogen-containing etchant; c) The step of removing the volatile by-products and the excess halogen-containing etching agent from the process chamber, d) A step of purifying the excess halogen-containing etchant by condensation, absorption, or a combination thereof in order to remove the volatile by-products and recover the excess halogen-containing etchant, and forming the recovered halogen-containing etchant, e) The step of returning the recovered halogen-containing etching agent to the process chamber for reuse, Includes, Step b) is a plasma-free thermal process. A method for recycling halogen-containing etching agents from dry development of photoresists.

12. The method according to claim 11, wherein the volatile by-product includes water, a metal halide, or a combination thereof.

13. The method according to claim 11, wherein the photopatterned metal oxide EUV resist comprises an organotin oxide.

14. The method according to claim 11, wherein the halogen-containing etching agent is hydrogen halide.

15. The method according to claim 14, wherein the hydrogen halogen is hydrogen bromide or hydrogen chloride.

16. The method according to claim 11, wherein the halogen-containing etching agent is trimethylsilyl chloride or trimethylsilyl bromide.

17. The method according to claim 11, wherein the exposure to the halogen-containing etchant in step b) is to an amount containing less than 50 times the stoichiometric amount of the halogen-containing etchant calculated to decompose the EUV-unexposed portion of the photopatterned metal oxide EUV resist into water and volatile metal halide.

18. a) Providing a photopatterned metal oxide EUV resist on a substrate layer of a semiconductor substrate in a process chamber, wherein the photopatterned metal oxide EUV resist includes EUV-exposed portions and EUV-unexposed portions. b) A step of dry developing the photopatterned metal oxide EUV resist by selectively removing the EUV-unexposed portions of the photopatterned metal oxide EUV resist by exposure to a halogen-containing etchant to form a resist hard mask from the EUV-exposed portions, thereby generating an impure excess of halogen-containing etchant, wherein the impure excess of halogen-containing etchant is a halogen-containing etchant contaminated with volatile by-products. c) The step of removing the impure excess halogen-containing etching agent from the process chamber, d) Optionally, a step of separating the volatile by-products from the halogen-containing etching agent by condensation, absorption, or a combination thereof, e) A step of collecting the impure excess halogen-containing etching agent by condensation, Includes, Step b) is a plasma-free thermal process. A method for recovering halogen-containing etching agent from dry development of resist.

19. The method of claim 18, wherein the excess impure halogen-containing etching agent collected in step e) is purified for reuse.

20. The method according to claim 18, wherein the volatile by-product includes water, a metal halide, or a combination thereof.

21. The method according to claim 18, wherein the photopatterned metal oxide EUV resist comprises an organotin oxide.

22. The method according to claim 18, wherein the halogen-containing etching agent is hydrogen halide.

23. The method according to claim 22, wherein the hydrogen halogen is hydrogen bromide or hydrogen chloride.

24. The method according to claim 18, wherein the halogen-containing etching agent is trimethylsilyl chloride or trimethylsilyl bromide.

25. The method according to claim 18, wherein the exposure to the halogen-containing etchant in step b) is to an amount containing less than 50 times the stoichiometric amount of the halogen-containing etchant calculated to decompose the EUV-unexposed portion of the photopatterned metal oxide EUV resist into water and volatile metal halide.

26. a) Providing a photopatterned metal oxide EUV resist on a substrate layer of a semiconductor substrate in a process chamber operably connected to a vacuum pump, wherein the photopatterned metal oxide EUV resist includes EUV-exposed portions and EUV-unexposed portions, b) Dry developing the photopatterned metal oxide EUV resist by selectively removing the EUV-unexposed portions of the photopatterned metal oxide EUV resist by exposure to a halogen-containing etchant to form a resist hard mask from the EUV-exposed portions, thereby generating volatile byproducts and excess halogen-containing etchant, which are then discharged from the process chamber via exhaust from the vacuum pump. c) The step of processing the exhaust gas from the vacuum pump to process the volatile by-products and excess halogen-containing etchant to form neutralized by-products and neutralized halogen-containing etchant, Includes, Step b) is a plasma-free thermal process. A method for processing by-products of dry development of resists.

27. The method according to claim 26, wherein step c) includes the step of exposing the exhaust gas to an alkaline spray treatment.

28. The method according to claim 26, wherein the photopatterned metal oxide EUV resist comprises an organotin oxide.

29. The method according to claim 26, wherein the halogen-containing etching agent is hydrogen halide.

30. The method according to claim 29, wherein the hydrogen halogen is hydrogen bromide or hydrogen chloride.

31. The method according to claim 26, wherein the halogen-containing etching agent is trimethylsilyl chloride or trimethylsilyl bromide.

32. The method according to claim 26, wherein, after step c), the neutralized halogen-containing etching agent is converted into a halogen-containing etching agent for reuse in step b).

33. The method according to claim 26, wherein the exposure to the halogen-containing etchant in step b) is to an amount containing less than 50 times the stoichiometric amount of the halogen-containing etchant calculated to decompose the EUV-unexposed portion of the photopatterned metal oxide EUV resist into water and volatile metal halide.

34. A process chamber having a substrate support, a gas recirculation inlet and a gas recirculation outlet, A halogen-containing etching agent delivery line coupled to the process chamber, At least a first condenser and a second condenser, each individually coupled to the process chamber, the first condenser and the second condenser comprising an inner water-absorbing liner material and an outer temperature-adjustable jacket, A recirculation line configured to connect the first condenser, the second condenser, the gas recirculation inlet, and the gas recirculation outlet, A gas stirring module connected to the aforementioned recirculation line, A vacuum pump and a vacuum line coupled to the process chamber, A controller in which instructions for processing a semiconductor substrate are set, the instructions are A photopatterned metal oxide EUV resist is provided on a substrate within the process chamber. The photopatterned metal oxide EUV resist is developed to form a resist mask by selectively removing a portion of the resist by exposure to a halogen-containing etching agent. The process gas and by-product vapor are introduced from the process chamber to the first condenser or the second condenser. The first condenser or the second condenser is cooled to capture water and form a purified halogen-containing etching agent stream. The purified halogen-containing etching agent stream is recirculated into the process chamber via the recirculation line. The controller and the code for An apparatus for recycling halogen-containing etching agents during the dry development of resists, comprising the following features.

35. The apparatus according to claim 34, wherein the gas stirring module is a magnetically coupled turbofan.

36. The apparatus according to claim 34, wherein the first condenser is configured to receive process gas and by-product vapor from the process chamber, and the first condenser is cooled.

37. The apparatus according to claim 36, wherein the first condenser is cooled while the second condenser is heated for cleaning, and water is collected to recycle hydrogen halogens.

38. The apparatus according to claim 34, wherein the first condenser and the second condenser are operably connected to the vacuum pump.

39. The apparatus according to claim 38, wherein the first condenser and the second condenser are located upstream of the vacuum pump.

40. The apparatus according to claim 34, wherein the inner water-absorbing liner material comprises anhydrous aluminum oxide, silica gel, aluminosilicate, or a combination thereof.

41. A process chamber having a substrate support, A halogen-containing etching agent delivery line coupled to the process chamber, A vacuum pump comprising a vacuum pump inlet line coupled to the process chamber and a vacuum pump outlet line for removing exhaust gas, At least one cryogenic condenser connected to the vacuum pump outlet line, A controller in which instructions for processing a semiconductor substrate are set, the instructions are A photopatterned metal oxide EUV resist is provided on a substrate within the process chamber. The photopatterned metal oxide EUV resist is developed to form a resist mask by selectively removing a portion of the resist by exposure to a halogen-containing etching agent. The exhaust from the process chamber is guided from the vacuum pump outlet line to the low-temperature condenser to recover the excess halogen-containing etching agent. The controller and the code for An apparatus for recovering halogen-containing etching agent during dry development of a resist, comprising the following features.

42. The apparatus according to claim 41, further comprising a trap positioned between the vacuum pump and the cryogenic condenser, wherein the trap is configured to collect liquid by-products.

43. A process chamber having a substrate support, A halogen-containing etching agent delivery line coupled to the process chamber, A vacuum pump comprising a vacuum pump inlet line coupled to the process chamber and a vacuum pump outlet line for removing exhaust gas, A detoxification module coupled to the vacuum pump outlet line, A controller in which instructions for processing a semiconductor substrate are set, the instructions are A photopatterned metal oxide EUV resist is provided on a substrate within the process chamber. The photopatterned metal oxide EUV resist is developed to form a resist mask by selectively removing a portion of the resist by exposure to a halogen-containing etching agent. The exhaust from the process chamber is guided from the vacuum pump outlet line to the abatement module to neutralize the by-products. The controller and the code for An apparatus for processing by-products of dry development of resists, comprising the following:

44. The apparatus according to claim 43, wherein the abatement module is an alkaline spray treatment system.

45. The apparatus according to claim 43, wherein the by-product includes a halogen-containing etching agent.

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